The right to say something is different than people giving material support to it. E.g., I will defend your legal right stand on the corner with a pro-holocaust placard. But anybody printing those placards or otherwise helping you is an asshole. I will happily tell them so, and I will refuse to do business with them. That's me exercising my rights of freedom of speech and freedom of association.

Freedom of speech isn't freedom from criticism. And it's also not freedom from any other lawful reaction. Anybody helping with Gab richly deserves criticism and shunning in the technical community.