What prompted me to start listening was a coworker bringing up the Oculus Quest 2. I pointed out that it required a Facebook account, and he was entirely unconcerned. I had known he wouldn't care, but it really got to me how little people value their privacy. I realized I didn't have any good arguments for why he should value his privacy.
For me it mostly stems from a worry that the collected information will be used for witch-hunts in a possible future where the US has fully fallen to a fascist regime. I recognize that most people will find this to be a stretch, but it's a vague fear I've always had.
@louispearson My rationale is a little bit more comprehensible to others (though only slightly): If my personal data is so valuable that companies are willing to give us a free account and then make BILLIONS off of our personal data, don't you think we should get a cut? Shouldn't I be able to make money off my own personal data? If I can't make money off of my data, some big corporation shouldn't be able to, either.