Substack is trying to become a new social media platform in the style of Twitter with its Notes feature, and with a mobile app with an awful feed (it's the only way to Pangram-check posts, which is unfortunately often needed). I'm using it now for my writing, reluctantly, because there are some interesting people there and it's possible to leave (it is still an email newsletter tool at heart and you have the addresses). But there's also a lot of verbose nonsense, echo chambers, and outright automated grift out there.

The paid side of it is just in poor taste. Almost inevitably, it leads you down the path to "read the bombshell beyond the paywall, now just $49.99 a year!" sensationalism.