You say that like there aren't hundreds of social media platforms out there now and like it isn't trivial for a technical person to set up your own social media service on some "bulletproof host" in Lithuania or Russia.

There isn't a dearth of social media. There are a couple of GIANT social media websites that have sprung up in the last 2 decades, but there are dozens of semi-popular niche-ier forums that cater to any rant you might want to leave.