> If we could agree on some kind of "low-tech web" (a subset of html, a subset of css, a subset of javascript -- or maybe no javascript at all?) then Dillo could be the champion of this.
There is a "movement"[1] called the small web (smolweb?) which basically does what you are describing without being so restrictive as Gemini. AFAIK Dillo should be able to render most of those features properly.