In other words, the most effective form of masquerade is the one where you discard the masquerade in favor of "oh, vampires are as normal as cars or gay people".
(Incidentally, this is the sort of thing science does all the time. This is, for example, how we discovered the atom.)
I've probably been reading too much Worm stuff, but I'm reminded of the "masquerade" about the existance of supers in that setting. There is no maquerade about whether or not supers exist; they're common knowledge, they have dedicated branches of law enforcement, and several are even well-known public figures. On the other hand, there's plenty of "masquerade" to be had on the level of "this particular person is or is not a super".
As far as I can tell, the thread is not focused on WoD, either oWoD or nWoD. I can't say regarding the conversation you're commenting on.
While the discussion itself is not based around either nWoD, or oWoD, those are the two settings that are the most famous for their use of the masquerade. For that simple reason, most of the examples will be pulled from those settings, meaning that they're going to dominate the discussion.
I suspect that you are correct, however--the single most effective form of masquerade may well be that there is no masquerade, and supernatural creatures such as vampires and other critters are just an accepted fact of life. In such circumstances, small-scale masquerades, that cover a village or a neighborhood, are probably the best that could be accomplished--just convincing people that there aren't any vampires
here would be enough to keep a vampire safe, I would think.
This assumes that the insurance companies are not actually owned by the supernaturals in question, which, given that this heavily focuses on the old World of Darkness, is unlikely to an extreme.
I feel like we've been over this before...the actors change, but the concepts remain the same...or maybe it's the other way around. My memory never was what it used to be, and as time has gone by, it has gotten worse.
However....
In this case, you're assuming a total dominance of all aspects of human society and economic activity. Anything less will, sooner or later, cause critical industries to come out from under the masquerade's control. The reason for this is simple: those insurance companies that are owned by vampires (for example) are primarily being used to maintain the masquerade--not to make money. Companies that do exist to make money will always have a cost advantage over those that are formed for another reason. The only reason why companies are ever able to survive existing for a reason other than making a profit is when there is either no competition (which will
not last in a global economy unless there is a
very good reason), or they are being externally funded. And it's no use saying that the vampires or whomever are maintaining control--new companies are formed all the time, and whomever
opposes the masquerade (and there will always be somebody who opposes it, for one reason or another) will start to take steps to protect those who are in a position to independently discover whatever the masquerade protects. This is leaving aside whatever measures the people who own these up-and-coming companies take to protect themselves, which will be substantial. At the end of the day, any masquerade that has the kind of influence you describe would be in a constant state of shadow war, as much with itself, as with any other. This is one of the aspects that WoD, both old and new, managed to capture very well--and that success, I believe, is one of the reasons why WoD has become the gold standard for all masquerades.
Yet even in WoD, the masquerade
does sometimes slip, even without outside help, and the consequences for those affected by a slipping masquerade are universally catastrophic--witness the vampire casualties in the witch hunts of the 16th and 17th centuries, for instance. Effectively, what contains the damage when the masquerade slips even slightly isn't so much the actual masquerade, or even the self-maintaining mechanisms that keep most people from seeing that which is hidden by the masquerade. What contains the damage is that the casualties among those shielded by the masquerade are so total that there is nothing left to use to track those protected by the masquerade outside of the immediate vicinity.
In the new World of Darkness, a lot of the supernatural is explicitly self-censoring. The Uratha have Lunacy, I'm pretty sure there's something which makes all but strong-willed people want to rationalize away the existence of vampires, and any attempt by Sleepers to seek to understand magic inherently destroys the magic, leaving only mundane explanations, because the Abyss exists. Oh yeah and you have the Exarchs who are willing to help enforce the Lie. Your actuarial tables won't make sense, because you are literally incapable of comprehending the mystic factor.
I understand this. You will notice that nowhere in this discussion did I say anything about eyewitness accounts, or Youtube, or cell phone cameras, or videos, or any kind of visible, easily accepted evidence. That can be countered, sequestered, marginalized, discredited, and, ultimately, removed. It would take a hell of a lot of influence, but it
can be done.
But science is a lot more than just YouTube and the nightly news. Science is about looking at something that you don't understand--something that you
cannot understand, or explain, or prove--and finding a way to explain things to such an extent that you can reliably predict what will happen in the future. That's what actuarial tables are. They don't require a belief, or even an understanding. They're just raw numbers, calculating probability, and the only thing that is required of them is that they work. And the problem is that numbers don't lie, or Lie, or indicate understanding, or anything else. Nobody has to understand magic, or thaumaturgy, or anything of that nature, to prove that it exists. They wouldn't even be examining the
possibility that magic exists. All they'd be trying to do is understand why a Kenmore boiler explodes in one house, and not in another, despite both boilers being put into the exact same situation, under the exact same circumstances. That's not understanding magic. That's just trying to figure something out--something that isn't possible under current, mundane laws of physics. If anything, the self-censoring nature of the masquerade will only
amplify the fact that this doesn't make sense, because it actively
removes the only logical explanation: that somebody actively tried to blow up the first boiler, and make it look like an accident. So what you get is a boiler that explodes when it should not have. If that only happens a few times, ever, no big deal. But if it happens more than once in a century, than it starts to cost money, and Kenmore starts looking into it seriously, to try to figure out what the hey is happening. And because sabotage is out, and our engineers are telling us that this is impossible, and our test engineers are duplicating the conditions exactly, and
they're not getting that result...well, at that point, you've eliminated all the mundane, reasonable, logical,
possible answers. You can't write it off as a fluke, because it's costing money, lives, and you're getting court orders to fix it. You can't figure it out according to conventional knowledge, because the primary factor that's making them explode no longer exists. So what do you do? You assume an unknown factor, and you move to isolate it, and when it turns out that any and all mundane explanations don't work, you're left with only the non-mundane.
if you were to try to break the cover of a Demon by doing so, you will probably either find one of them convincing you that everything you found out was wrong, or find yourself strapped to a chair, being tortured by a bunch of hardened cyborg terrorists until you signed away your soul, and the next day, why, it turns out you made a basic mistake in all your calculations and there is definitely no such thing as the supernatural! In fact, it seems that I'm a complete lunatic! Or says the demon puppeting your very identity because they just erased you from all existence and now they've taken your place. And even an institutionalized crazy is a useful Cover because if nothing else, you can Burn it.
How does the demon know you're investigating him (or her, or it)? Remember, nobody's asking any questions of the average passer-by on the street. They're asking questions of men in white coats, who have labs full of explody things, and who everybody tends to
really notice if they go insane.