Yeah that really sucked. It was a great volunteer platform and I was sad the guy sold out. It didn't filter anything. Not rich guys' jets, not military etc.
The community never really recovered. The airplanes.live one doesn't have as many feeders and the airframes.io is hidden behind a login.
I was hoping the community would simply move in unison to a new platform just like what happened when freenode got ruined. But it seems to have kinda fallen apart.
Especially the MLAT abilities (receiving traditional transponders pre-ADS-B) was really cool but it really needs a lot of feeders to be able to pinpoint them.