In many ways, Mastodon feels like rewinding the clock on social media back to the early days of Twitter and Facebook. On the consume side, that means that your home feed has no algorithm (this can be disorienting at first).
Practically, it means that you see only what you want to see and only see it linearly. You never wonder “why am I seeing this and how do I make it go away?”. Content can only enter your home feed via your followed tags or handles and the feed is linear like the early days of social media.
“Influencer” is just a word to describe a phenomenon that will naturally arise on any platform where following someone doesn’t require a follow back: some people will have a lot of followers, for whatever reason. They’ve existed as authors and columnists, radio personalities, television and film celebrities, podcast hosts, etc.
Some grow followers organically on the specific platform, while others bring their followers on from being independently famous outside the platform. And it doesn’t matter if they don’t start off as famous - all it takes is for a post or comment to go viral and then the attention is there, whether the creator wanted it or not.