He's arguing that Medium owns the distribution rights to your content. Which... if I were to be partial to him, I'd say Medium can monopolize the public's attention as to where we read content. Like Amazon and Books, PornHub and Adult Videos, probably others. It's possible that if Medium goes under, it does everything it possibly could to prevent people from downloading their content.
Not saying that I agree with him. At the end of the day, Medium says the writers own their content. I feel ok with them, though I can empathize with OP, given the amount of shitty things BigCorp companies have done in the past.
https://medium.com/policy/medium-terms-of-service-9db0094a1e...