I followed you for a while, and liked your work so much, I hit the email me when you publish button. I limit myself to 20 writers.
I think that email button might be the key to measuring engagement and serious readers of your work. I read almost every Medium articles that comes in via email and very little else.
I think Medium is having trouble trying to figure out how to attract and keep readers. If so, readers' ability to curate all the writers here is a key.