Congratulations on the release!
I have enjoyed working with htmx very much.
I'm still skeptical of htmx being the foundation for a 100-year web service, but I think this is a really worthwhile goal. I'll add that aside from static HTML, I don't have a better option.
Thinking about how well your web architecture will hold up for 100 years (or even 10 years) is bikeshedding and a pointless exercise.
Perfect is the enemy of good and all that. If something is useful, it’s possible to fix the architecture later. The only counter-example I know of has been GitHub, which was built on RoR and so poorly planned that it’s still biting Microsoft on a regular basis.