You hit on something I think about frequently: when writers threaten to start using another platform, my response is usually "... wait, you're not already using that platform??"

Medium is designed to be a complementary platform. As a writer and publisher myself, I would never EVER put all my eggs in one basket -- even if it's a great basket! My publishing company was built by having numerous ever changing revenue streams... different platforms, different partner programs, numerous strategies. For me back in the day it was WordPress, affiliate partnerships, a vendor directory, annual sponsorships, third party ad networks, at least 3 social platforms, downloadables, etc etc etc. I'd NEVER suggest anyone be completely focused on one platform ... so when writers threaten to go elsewhere, I'm always like omg YES you should definitely do that! Medium is here for you, AND so many other great platforms are great too! Writers leave, writers come, writers diversify, writers come back... it's all a natural, expected part of the flow of how creative folks do their work. I love it all!