What does it tell you (see description) about Medium's customer profile?

Medium.com has following categories (same order from left to right) :-

Culture, Humor, Tech, Design, This Happened, I.M.H.O., Long Reads

It does not have,

Business, Politics, Spiritual and a bunch of other possible categories. It does not mean that people don't blog about them, it just means that they wont get featured.

I thought this question could solicit some interesting answers.