As a dev, another really cool development to me is the introduction of ActivityPub to things like Gitea, and forgejo, again this is really where the concept of federation just kicks ass to me. Like imagine commenting on code issue, on lemmy/mastdon/discourse? No need to setup webhooks, bots, webscrapers. Just native support for cross-platform discussions.
Want to follow latest releases of your favorite FLOSS projects? Just follow their repo! You can crosspost it or boost too if you want to.
Same reason I want more forums like Fedora Discussion, Ask Ubuntu, and Stack Overflow on the Fediverse. I like the Fediverse as a way to see information and have discussion on it. More good content, the better. Without good content, I would never have used Reddit in the first place.