100% agree with feeling that 'something' early on when joining Medium. There is just something about the community here that stands out. I've dabbled with other platforms but not felt the same spark.
Vocal to me seems flat. There is no character and is kinda boring. I've been a paying member a few times on Vocal but for no longer than a month at a time.
I haven't tried Bitclout or Substack yet but did have the free version of Quora and it just wasn't for me. The app felt too chaotic with too much going on which put me off from the start and never inspired me to spend time learning it.