With Mastodon you can follow hashtags. I primarily do this instead of following people's accounts because most people post on a variety of topics when I'm only interested in probably one of the topics they post on. This gives me a very high signal to noise ratio and I get to see any post with hashtags I am interested in instead of just the ones by people I'm following. If someone misuses a hashtag, I can simply mute their account and never see their posts again.