Gemini is basically an alternative web, so it has its own protocol, own server and browser software, and an own content language (heavily inspired by Markdown).
Everything is built to be much more lightweight, so certainly in the spirit of solarpunk.

But big downside is that "the thing you want" is honestly probably not on Gemini at all, because it does not share content with the HTTP web.

That does mean that all the ads and bullshit are gone, too (and cannot be implemented beyond static images, sponsored articles and I guess, ASCII art).
But yeah, at this point, it's most useful for reading (and writing) blog posts, and having fun with the technology itself. It does have a lovely community for that.