That makes sense, but my case is before I know who to follow. Is there any way to explore what’s going on on a server? Like browsing a news group on Usenet or checking a subreddit before subscribing?
How would you do that on Twitter? Follow the hashtags. Why do you insist on limiting it to a server? That's not really how it is supposed to work anyway, it's not those things you mentioned.
Otherwise for someone who posts frequently and has a good following, then it's probably worth it to start posting on Twitter and Mastodon at the same time, that's the only way it happens. Big movers and shakers are either going to stay on Twitter or drag everyone else with them, basically unlikely to happen.