I honestly believe that some people do not know when their writing has little depth, or is difficult to read. I spent over 2 years working at an indie publisher, and omg, that’s the biggest takeaway. The amount of truly weak writing I saw was painful.
That said, like most other things, writing is a skill that we can only learn 2 ways — by reading and writing.
In that aspect, Medium is a terrific tool. When a writer looks at their read rate, and sees that some have 85% read rate and others have under 50% after a while perhaps they will begin to learn what good writing is.
The biggest mistake here is to assume that lots of hearts mean good writing. Good writing can get a lot of hearts, but good writing can also be lost in the shuffle. Bad writing can get lots of hearts when the writer has a big enough following.
But read rate, that’s where the rubber meets the road. Just my 2 cents. :)