> Let's be real. How many users care?

I think this question is very context sensitive. The way privacy questions are usually presented ("we want to improve/personalize your experience"), I don't think most people care. But when presented with actual outcomes of loss of privacy (e.g. the Cambridge Analytica scandal) people seem to care a lot. For most people I suspect there's a gap in understanding between how people think their data is used and how it's actually used. Whenever this gap is closed by a major scandal where "how the sausage is made" is revealed, there's often a strong reaction.

But perhaps the biggest indication that people do care about privacy is that ad companies are so reluctant to allow them to opt out of tracking. If (almost) nobody cares, what's the harm in having clear consent or an opt out?

Lots. I have yet to come across someone who didn't care, after they understood what was happening. Virtual anonymous people in forums don't count ;)

Not one person I've asked has responded that they would be willing to post their entire browser history on the open internet.

I care a lot, and I like having the option to make the choice on a cookie banner and use it.