Get your hands on a random selection of 10 iPhones and look at the apps installed. I suspect you’d be horrified. As an example - any parent who has installed a free game for their kids likely has all of this info, plus more via tied in logins.

That said, I agree with the rest of your point - you’re not going to go to a developer and offer them $100 for this data on a person (and if you could, you’d still need to tell them which person, which if you could do you could just get the data yourself)