You're missing entirely what I was trying to say. I was saying when does said pragmatic thinking within the Worm-verse draw the line as far as what's acceptable to just ignore for the sake of "Usefulness".
And yeah, Bonesaw is a prime example of one that MOST DEFINITELY crossed the line for me.
Well, in reading through Worm, the major thing that got you punished (through Birdcaging or vigilante justice) was in making Endbringer fights less winnable.
Now, your supervillain argument didn't make sense because of the following: Making Endbringer fights less winnable is not simply about bodies on the battle field. It's about morale, a faith in the rules of the truce, and a belief that the fights are worth fighting.
Tattletale actually discusses these things when she gives Taylor advice about the PRTs motives (anyone remember specific arc numbers?)
If less than heroic capes start thinking that the PRT is going to punish them no matter what they do, then they have no incentive to do anything other than ske-fucking-daddle when Endbringer sirens blow. So the PRT/Protectorate unofficially assures them that there will be unofficial leniency for participants, thus ensuring more cooperation (of course, villains have families, businesses, friends, etc and might have a motive to participate
anyway but they're more likely to work with PRT/Protectorate forces during the fight and immediately after).
In return, the villains make it clear that they won't abuse the trust system, especially since the PRT/Protectorate/EVERYONE will come down on them for metaphorically shitting in the allegorical swimming pool.
This system actually pretty closely mirrors real world moralities (albeit undeveloped ones) as envisioned by
Lawrence Kohlberg, a Piagetian psychologist, in that the villains can really only be counted on to do things that benefit them (but then again, so does Armsmaster at first, so....). But I digress.
The people who are 'crossing the line' are the ones who fuck up the system. S9 is an example, because they won't play by the rules. Heartbreaker (presumably, and any Heartbreaker-like Master) is another because he can't be trusted to not take advantage. Any cape who prevents the truce system from working are those who outweigh their usefulness, because they make the entire system fail.
This is not the ONLY line in the sand in the worm-verse. Obviously, people get Birdcaged for other things, like murder, but there is definitely still some wiggle room in those cases. Lung for example, is the only cape to go toe-to-toe with an Endbringer. He's probably killed people personally. The Protectorate doesn't come down on him though, because the cost to defeat him vs. the benefit to having him show up to an Endbringer attack is pretty unbalanced. Notice however, that the moment he gets taken out by Taylor (no cost for the Protectorate), at which point it's clear he doesn't plan to participate in the Endbringer fights (didn't show up for Leviathan in BB, right?), he gets Birdcaged
toute de suite. There's definitely a line graph someone could plot of x) cost to apprehend/contain vs. y) utility of power/skillset. Bonesaw is a great example of that: as a medical tinker, her involvement with the Protectorate increases everyone's effectiveness by exponential leaps and bounds. Of course, given that her involvement comes
after the Endbringer threat is dealt with is definitely more.... morally questionable. However, she's also a child with severe PTSD and Stockholm Syndrome, so cut her some slack maybe.
So yeah, the Protectorate is definitely super duper pragmatic, probably to a fault (and this is addressed in universe by various characters, including Taylor) but they're also operating under the assumption that they're all going to die otherwise. And the higher-ups know about the space whales who want to eat us. So... yeah, I guess if they are literally weighing multi-universal earth-wide extinction against ignoring someone being a murderer/torturer/etc (yes, even with a kill count in the triple-digits, because 999 is still less than 7.125 billion x however many earths there are by several orders of magnitude), then they might just let that guy slide.
Until he fucks it up for everyone else.
