Earlier quoted context omitted.
these questions are in earnest, not meant as a put-down of your position. how would you draw a line between what's okay to collect and what isn't? do you think a line could be drawn that would work for most people? would sites offer different levels of invasive tracking, and the user opts-in as far as they want? what incentive would users have to opt-in at all?
I think the line drawn would be easy: they cannot collect the data themselves, they can only use what you fill in on a form they present. Then the line is basically whatever you feel comfortable telling them, knowing it will be used for advertising. The incentive would be the standard reason ad companies give for targeted ads: given there are going to be ads, people would generally prefer they be relevant.
Now, let's say I own an apartment block and want to advertise for tenants, but I don't want any of them dirty muslims in my building. I can target my advertising to exclude people whose interests include Halal food.
Or, let's say I'm the propaganda department of an adversarial nation state, and I want to stir up communal tension. All I have to do is find people with an interest in Halal food, and target them with ads exhorting them to join other Christians in the next Crusade against the Moors. Or whatever. This was actually a common technique in the 2016 election: identify voters who, via their social connections and profile interests, are likely on the fence about Clinton vs. Trump, and also are a bit homophobic -- then target them with "Queers for Hillary" advertisments.
It's shocking how easy it is to weaponize this stuff.