It's based on more than merely a Twitter statement, and as far as I can tell, the guy is still a member (though he has no more official responsibilities). Aaron König, another prominent (in his case: former) pirate had his own crude and/or right-wing extremist views. He now spreads them from a new populist right-wing platform of the Geert Wilders kind. Despicable people, all around.

All that said, I agree that it's unfair to condemn the PP because of those individuals. They're far from the norm.