Hashtags have been pretty helpful to me on Mastodon. If people tag their stuff with the tags I follow I get a chance to see me stuff and follow new people organically, while people who didn’t want to be discovered never hit my radar. Making that kind of topic tagging easier for people to apply might be useful, as I’ve seen new arrivals to the Fediverse who can’t figure out why nobody sees them until someone tells them to tag their stuff.
If I see a post and I want to see more posts like that in that community, I updoot. If I want to see less posts like that in that community, I downvote. Nothing more complicated than that.
So if you post a cute cat pic to a community about cats or cute things, I’m updooting it. Not even super concerned with how well I looked that specific pic, I want to see cute cat pics there and you provided one so you get the updoot.
But if I’m in a discussion-based community and you post something with a clickbait title, I downvote. Doesn’t matter if you’re technically still on topic, I want to see less of that nonsense so I downvote it.