Other than the odd writer promoting his own work (like myself), I haven't seen much advertising on Medium.

I've been here since April 2019. From what I've seen, Medium is a writer's forum. Most of us want to be read than to read. I don't believe that there are thousands of readers who come here just to read on a regular basis.

As for quality of writing, I see four levels: Poor, Competent, Good, and Great. Other internet forums have lots of Poor writers, but I can count the truly Poor articles on I've seen on Medium with two hands. Those in Competent can explain things somewhat well, but probably won't make a living in writing. Good writers have the ability to make a living, but there's a big element of luck to take them to that edge. So it is with many creative professions. It's that supply and demand curve working its magic.

Good writers do become popular on Medium. But how these good writers are selected over other good writers to be popular is a mystery to me.

The Great are only a few. Some of them are not popular. Right now, I would put Benjamin Sledge as a great writer, someone who could rival Hemingway some day .