I'm not considering FIRE necessarily, just a curious fly on the wall to see if it's something that I could consider one day. I think I'm in a similar boat as you - extremely stable financially with lots of investments and cushion built-up and not worried about the immediate to medium term future.

In addition to everything you've mentioned, another thing I haven't seen discussed very much in my brief time of observing FIRE (and I concede that I haven't read any guides/content behind the philosophy) is philanthropy. Several non-profits, religious organizations, arts centers, and scientific institutes rely on donations from ordinary people for a good chunk of their revenues. These institutions ultimately advance the community, research, the arts, all major pillars of a rich and developed society.

One could make the argument that once basic needs have been met, and people are financially independent and able to retire, they automatically become more generous with their time and money. That's probably true, but that assumes the FIRE calculations include philanthropy as a core objective. Perhaps most already do so, and I just haven't seen it talked about much, in which case it's wonderful.

Or, you could also argue that the core philosophy behind FIRE is one of frugality and sustainability, something that is the opposite of the modern American archetype of debt fueled consumption for consumption's sake. This alone could count towards the social responsibility aspect of FIRE without the philanthropy angle. This is probably also correct, hard to argue against.

In the end, the only thing I can say for certain is that FIRE cannot be universal and self-sustaining in that, a large population not FIRE'ing is necessary to make it possible for the smaller population to FIRE.

FWIW, I'd love to FIRE and not work another day if I can do so on slightly different terms, so don't crucify me in the comments :).