Reddit's become mainstream, it's quoted by serious news outlets, joked around on Last Week Tonight (and other politic joke shows), and I'd say it's as likely to disappear as Facebook. Which is to say, surely but very slowly.
Everything Criteo says is just terrible. They're about as borderline legal as it gets. I'm 100% expecting them to get massive GDPR related fines in 2020.
Did a side hustle in a startup for a while, and for us a conversion was a user signup. Facebook ads were _really_ cost effective. Every time we ran a small batch of ads at our audience segment (professionals of a specific discipline in a couple of geos) we'd get a lot of signups, way more than by any organic means (which also have a cost, just not always translated to cash).
I think this is only on fake-scenario. In a real DMP, the user would be "loves cola","loves coca cola","loves fizzy drinks","drinks sugared drinks", and about 30 other related segments, and one of those would definitely sneak by.
Humans create audience segments, and it's in the interest of dataset producers to have each user be a part of the maximum number of members they can be to maximize monetisation.
Another 5 year adtech worker here (and I'm still in it): it doesn't matter that it's a handful of large companies that have PII, it's that those companies keep getting more and more of adbudgets, and continue to build more and more products towards continuing to build real profiles.
When did you see anyone on TV mention Digg?
Reddit's become mainstream, it's quoted by serious news outlets, joked around on Last Week Tonight (and other politic joke shows), and I'd say it's as likely to disappear as Facebook. Which is to say, surely but very slowly.