Platforms are not private companies
Recently, a lot of platforms banned people who happen to have the wrong (right-wing) views.
In defense of these decisions, people typically use the right wingers' arguments against themselves:
But you say that private companies should be able to do anything they want. So you should be okay with them banning you.
Yes and no. Someone might argue for A, B, C, D, but you can't force them to accept, say, C, just when it hurts them, without having all of the other points.
To make that less abstract, someone economically right might argue for a lack of regulations, lack of government funding, a simple tax code, and the ability of private businesses to choose who they do business with.
You can't say that someone should accept being banned from a platform "because that's what they stand for" when the platform didn't exist in a world that has a lack of regulations, lack of government funding, and a simple tax code.
In this specific instance, those three things benefit the platforms and prevent competition. And the argument that companies should be able to choose who they do business with depends on pro-competition policies. If you won't serve someone because X, someone else will, and they'll get his money — your loss.
In this case, if you don't have access to FB and Twitter, you have access to virtually nothing.
So the use of this argument against people who favor (classically) liberal economic policies is not only wrong, it's hypocritical, since it's coming from a place of trying to prove how the other person is hypocritical.
Hell, that's not even hypocritical, that's recursively hypocritical.