Being courteous, thoughtful, and taking best-faith interpretations are key aspects of the ideology that is mandatory under this site’s guidelines. This is a wildly unpopular ideology at other sites.
If a user or mod noticed them breaking those guidelines over time, and they continued doing so after being repeatedly warned, then they absolutely would have been banned for their ideology.
Otherwise, I don’t think anyone really cares how disagreeable their viewpoint is, so long as they’re courteous and contributing while expressing it (and it’s not derogatory, hate speech, etc).