You definitely could, but it’s not really sustainable.
Worst case scenario: if everybody does this, and there’s 50.000 subscribers on a certain community, then that community will have to update 50.000 other servers whenever one user leaves a single message or vote.
Sure, your own server wouldn’t have a hard time, but it every popular server (with lots of subscribers) would. It would either take a long time for you to receive their updates, or you wouldn’t get them at all.
The best thing you can do, is join a medium size server: it won’t be as overloaded as a big server, and wouldn’t cause as much strain on the fediverse as a personal server.