It's kind of a trap, but Medium definitely provides the audience. The articles I've written there have gotten way more reads and interactions in the last 2 years than anything I've ever written on any other blog I've had, and it required no SEO or paranoia over whether there's something about my markup that Google has decided it doesn't like.
The reason that I say it's a trap is because I think search engines, especially Google, don't seem to index things as easily as they did in the past. Any time I host a new site, it can take months for it to surface in search results, and even then it might not even show up in other people's queries which seemingly depends on the age on a site and whether Google's algorithm subjectively likes the content. But Medium has been around for a while and your articles appear in search results in mere days, sometimes less than a day. It's a trap because we're made to believe that we can't or shouldn't host our own material.
I would prefer that we wouldn't have to use Medium, but Medium has a product that delivers, and it's not the scam that people are making it out to be.