The main goal of these sites is link aggregation. It wouldn't be overly difficult for a federated server with its own /c/Technology community to see other posts from other communities linking to the same thing and combining the discussions into a single view.

The tricky part there is moderation, but even that's manageable by allowing moderators to remove content from a federated view within their own instance, it'll just be difficult when a small instance is dwarfed by a larger one.

Freedom of speech is never freedom of consequence. And if that consequence is that nobody wants to listen to you, well that's on you.

I think this has always been the case, though. Engines haven't just suddenly got better, they've been getting better and better for decades now. Some of those improvements give you features "out of the box" that you used to have to implement yourself. One of the reasons Unity became so popular with smaller developers is because it lets you focus on building your game - most of the tech is there, you've got an asset store for additional models, plugins, etc. so save you time but ultimately making a (good) game still takes time. Making a game is a very iterative process and a lot of the quality of a game these days is less to do with developing the engine and more to develop the mechanics of the game itself - the way your characters move, the responsiveness of the controls, the UI layout and so on. All of that stuff is hard to be given to you by an Engine, because it's specific to your game.