My personal view is that if you take a personal, not a preaching stand early and often people just learn that's who you are. I've never had a Myspace or FB or IG, or any other sort of account like that. To all of the people who say they can only stay in touch that way I just said, "I'm available via text, phone, chat group, Discord, email, Signal, and half a dozen more ways. If that isn't easy enough then maybe we don't need to keep in touch."
The only reason I can imagine seriously engaging with those things is as a business owner who watched FB railroad them into advertising there or being screwed, and happily I've never been in that position.
So yeah... at some point you have to accept that most people will happily dig in, and even most people who have qualms will find ways to justify why it's ok FOR THEM. You just have to make your own choice and stick with it, firmly and politely.