It would probably be more accurate to say that for some time, his politics (opposing the Iraq war & the surveillance state) looked sympathetic to many people. His later embrace of Trump & Putin rather undermined the idea that his politics was based on deep libertarian principles.
But in reality he had already done some fairly vile things by then already, e.g.:
* Defending murderous Neo Nazis (not vile in itself, they need lawyers too) while calling their victims “odious and repugnant”.
* Running escort websites and producing cinematic masterpieces such as “Piss Boys in Love”, both with the involvement of his then-boyfriend and later husband David Miranda, under circumstances that seem rather exploitative of the Brazilians involved.
Defending your client is not vile, and making statements that contribute towards that defense is part of the game, even if they are harsh.
Funny to see someone who seems to be on the left engaging in “kink-shaming.” Glenn has the right to a personal sexual life, including whatever exotic sexual proclivities he may have. Frankly, the film you mentioned sounds pretty tame for gay porn.