I really love that idea a lot. Just to start it would be great if there was a record of the url and even just one short sentence about a site. Just to start. Just to ensure they don't disappear completely.
Do you have any examples in mind? As much as I love the smol web, because we're all over the place there isn't a great way to just ask "hey does anyone remember anything about 'gemini://example.com'?"
By the way, the domain you quoted there is available for purchase. Pretty cool name for a site. :)