As I wrote in my example, this intent based method works for a big advertiser which is making a mass market product; but say someone producing a niche artisan knitting needle which only say 1 in 100 people who are interested in knitting needles will be interested in, would benefit from targeted advertisement. Otherwise, they would end up spending a lot of money on ad space not worth bidding for.

A nitpick, the advertiser is not collecting and getting PII. FB the ad platform, owns and controls that data.