There is a huge difference between a platform censoring/banning you and a community on the platform censoring/banning you. No irony involved. That subreddit is just trying to have discussion among like minded people without trolls and brigaders disrupting everything, they are a highly targeted subreddit for those acts. Reddit as a platform still exists for you and joining or making new communities is possible at the click of a button. Contrast that with having to create your own platform which is prohibitive, or migrating to another platform (if one even exists), which is also prohibitive.

And now we have a most recent grievance of a group getting removed from all platforms, creating their own platform, only for it to be removed from existence by mobile devices and web infrastructure dropping it.