looks like rendering adblockers extensions obsolete with manifest-v3 was not enough so now they try to implement DRM into the browser giving the ability to any website to refuse traffic to you if you don't run a complaint browser ( cough...firefox )
here is an article in hacker news since i'm sure they can explain this to you better than i.
and also some github docs
Sure you could make the argument that HTML has too much going on, but you don't have to use all of that. It is still at its core just as capable of rendering plaintext and hyperlinks as it was the day it was originally conceived.
Why couldn't this just be a webring of sites that are following a specific design philosophy. I don't understand the requirement of an entirely new language, protocol, and client. You're not executing the goal in any way than what is already possible, and you're cutting yourself off from being accessible by the vast majority of people by requiring them to install a whole new piece of software just to see if this idea is worth exploring.
The people who designed Gemini (and those who designed Gopher, and who did IRC, and...) have already gone to vast lengths explaining why it has to be redesigned from scratch, including new language and protocol. tl;dr: if you keep using current HTML, you have no way of preventing people from using eg.: