I can't exactly speak for
@Imrix, but, mm...
There's a quote from the Nasuverse fandom (yes yes) that I think is relevant here. "Magecraft is 'how did you do that', Magic is 'what did you
do.'" The context isn't relevant at the moment, but there's a distinction there that's stuck with me, even so.
"Magecraft" is sort of like science fiction. It's comprehensible, it works on principles we at least think we understand for the most part, it just works on a scale - in size, in energy, in efficiency, in precision - that's far beyond the current day. It's
impressive, but it's "merely big".
"Magic" is something else entirely. Magic is conceptual effects (well, not in the Nasuverse, but this is the Exalted thread and I'm using it as a metaphor.) Magic may or may not achieve things you could achieve through technology - but the way it does it makes you step back and take a minute, gives you a moment or two of incomprehension. "Kill 'the state of a burst appendix'", "change your Name and thus disguise your identity no matter how paper-thin your disguise" - or, yes, "make it physically impossible for someone to
not find a tutor for Sorcery." Magic is something new.
Part of what makes Exalted cool, for me, part of what makes it interesting as a setting, is the way that it treads on Magic. Because
I'm a physicist, that's my day job, and so I know just how much is within the limits of "what's hypothetically possible." I work on cosmological scales all the time. It's impressive, if a human - or Exalt - learns to work on those scales, but it's ultimately "merely big." It doesn't leave me in awe, it doesn't leave me breathless, it doesn't
make it seem like an Age of Wonders, just because the things they make are bigger than the things we have. I want
new concepts, I want
new ideas - or things that just can't be done through technology.
Most settings don't do that. Even the most powerful wizard tends to just make very pretty lights in very large spaces. Exalted has perfect defenses and Dodge Charms that work on lawsuits; that's a very large part of what drew me in in the first place.
So of the ideas listed, the closest that I could consider as "deserving to be in the Age of Dreams" is the country with zero robbers. Most of the rest are "merely big." And most of the, mm, the broad scale conceptual effects, the sort of abstract Magic working... they're going to have serious mechanical implications. Maybe you can draw the line before you touch Enlightenment minima - but it shouldn't be
too much before that, because the Exalted have already demonstrated the ability to interface with and manipulate the abstract, and a whole lot of that is going to end up looking like "painting the fourth wall" in practice.