Discrimination is a broad term, typically used to indicate an individual person is being discriminated against based on their membership of a group of similar persons which usually fall around race, age, sexual orientation, etc. Discrimination, outside this context, means "recognition and understanding of the difference between one thing and another". A company cannot be discriminated against while applying an individual person context because they are not people.

There's exactly one person being discriminated against here and that is based on the business they run and the relationship they had with Coinbase. Coinbase, and Brian, have every right to limit their business dealings with Gab, and can do so without it being "discriminatory" in nature. Arguing otherwise may be considered an attempt to control the conversation in a direction that leads away from logic.

Well personal disclosure I'm pretty staunchly left so I'm not going to lie, I think It'd be pretty bad of a business to discriminate against those groups but I think at least the case can be made that those groups have the potential to disrupt the platform and everybody else on it through their political activity, so I think the owner has some legitimate discretion.

I do agree that there should be basic protections on private platforms for speech, especially if people are threatened to be excluded based on ethnic or religious or apolitical identity. But I think it would be absurd to say, if a company could not shut down a threatening or violent, or otherwise outside of the norm organisation.

There are businesses that do discriminate against those groups. You don't hear much about it because they're usually small businesses that can afford to alienate people who aren't their customers.