messenger, whatsapp and instagram. And of course they're relevant because if Facebook employs these tactics on one site there's no reason to believe they won't do equivalent things anywhere else. They own the largest competitors to their own products, obviously that's relevant because it shows how strong their grip is and that there's no genuine alternatives.

"delete it" isn't a solution at all. You may as well say "turn the electricity off". People deserve privacy when services are provided to them by private companies, that's not a bonus, it ought to be a fundamental right. It's not the job of individuals to take on trillion dollar multinationals.