If you lie down with dogs, you get up with fleas.
What possessed this guy to think he could associate with facists?
What you highlight (promotion of off-Twitter websites) is exactly why they booted him without saying why.
My bet is that they determined his success was a net loss of users for them. People found his website and bookmark him and never came back to Twitter.
So they gave him the boot, his being conservative was an added motive, but the real reason would be loss of users.