I feel your pain. My history on Medium: I just set out to write at first but was compelled by the idea of making a bit of money using a talent. Even when I failed to get claps or followers, I still enjoyed writing. And I got good feedback. I became a better writer, thanks to Medium. I've not made much money and I do work another job.
I didn't want to slack at my other job so when writing was calling me, many times I had to ignore that very loud voice.
When you pull away from Medium you have to rebuild. You even have to rebuild friendships and make sure you know which pubs are the best for your writing
And it's easy to feel invisible.
I am currently working to figure out the answers to some of my questions. Working on a few new stories, etc. But I'll still publish on Medium. Not many choices out there
Can substack work for you? I don't know anything about it. I do, optimistically, believe that eventually Medium will free it's writers from its oppressive rules.
Good luck to you. I'm going to follow you because I want to hear what's going on in a few months.