I definitely suspect that a lot of folks have flooded Medium because lots of people want to make money as a writer. Medium basically removed the gatekeeping for monetized blogging.
My thoughts on writing are about the same as my thoughts on making music. If you’re doing it to make money, you’re probably shit out of luck. If you’re doing it because you enjoy doing it, then keep doing it. Enough people enjoy it that they’ll do it for free, which floods the market. The idea of being a professional writer (or a professional musician) is quickly becoming a losing game.
I write stuff to get the weird thoughts in my head out of my head, to help me explain things to myself, and to clarify my own thoughts. It’s therapeutic.