> as no one is arguing that any corporate entity simply has the right to exist

Yes, but I do still see people give the "just don't use FaceBook then" argument on every post about this on HN, as if we should just ignore all the problems. Under this insane framework any horrible behavior by a company towards their customers is justified as long as you use their products willingly.

This also ignores the massive existing adoption FaceBook has. If I want to switch to twitter or mastodon or $otherSocialNetwork I have to convince everyone I communicate with on FaceBook to switch too.

Regardless of user demand, many businesses and business models are still illegal by popular acclaim.

User demand is a necessary but not sufficient condition for a business to exist.

In this case, you could argue that the "users" is almost equivalent to the people (of EU), because of how widespread the usage of Facebook is. What we see here is that the people is starting to decide that some things that Facebook are doing are not acceptable anymore.