However, if you don't care about monetizing your content, want full control over your content, then it's not that hard to start your own single publisher website - either developed from scratch or using some existing solution like Wordpress. You could also simply post your content on places like Reddit, HN, Lobsters etc. One more thing - you can try sending your blogs to local & national newspapers as Opinion pieces - this has less chances of being accepted but worth trying.
Personally, I absolutely hate medium simply because of how slow they are, how they push their popups everywhere as well as censorship. I am a paid subscriber to multiple substacks as I want ti support independent journalists - Glenn Greenwald, Matt Taibbi, Michael Tracey, Aaron Mate. I also regularly read Abigail Shrier, Bari Weiss, Caitlin’s Newsletter, Karen Hunt etc.
I wouldn't create an alternative to Medium, because I just think it's the wrong approach. We know the answer, because it's what everyone had no choice but to do before: run your own stuff, host it yourself, own your own domain, have your own process, keep things much more under your control. RSS.