Not a publication. You have to dig and hunt through a publication and hope you can find the right article that will tell you the information you need. If I were a new subscriber and had to dig, I would be gone.
I would like to see a categorized and alphabetized Medium Help section of webpages that tells you how to do things, such as how to tag your posts, how to submit to a publication, and so forth. A search function in the Help section would also be nice and would make having a Medium Help publication be much more tolerable.
There needs to be something that clearly explains the algorithm--unless they are leery of people trying to game the system, which concern I would understand. There are clearly writers here who would game the system if they thought they could; I've encountered a couple.
Mainly, I would want to see something that explains how articles are distributed for viewing. It would be nice if there was also a stories search tool exclusively for the Medium site--not for article titles, but for topics.
Clearly, they need to implement a help desk if they are losing subscribers for the lack of one. A live chat would be fine.
If new subscribers are so displeased with Medium that they are unwilling to spend even $5.00/month on it, then they are extremely displeased. I hope Medium will strive to correct the issues.