I don't actually know how important engagement is in gaining readership, but I have quite a lot of followers. I don't remember off the top of my head, but it's somewhere north of 25k.
I set aside two to three hours every morning to read and engage with stories on Medium. I read a few people like you, just because I've gotten to know them and I'm interested in what they have to say on a personal level.
Mostly though, I just look for stories that pique my interest. When I read something I enjoy, I try to clap, highlight, and comment — because it seems like the nice thing to do. Like the least I can do to express my appreciation for the work they put into the story.
I understand some writers feel they don't have time for that, and probably they're right. Not everybody is semi-retired like me and has the kind of free time I have.
But sometimes I do wish that more of us would take a little more time to read and engage, when we can.