I've only read this last page, but I wanted to make a small point: catfishing doesn't necessarily have to mean you're using someone else's picture. Someone can say they're from a completely different area, with a completely different name, and say they're really into this thing that you're into even though they aren't.
Snapchat doesn't necessarily always have location info, so someone could tell you they're in New York when they're really in California, and you wouldn't know. Same with Facebook, you can list yourself in another town or state. I have a friend who lives with me who has his location on FB set to a town two hours away (not for any nefarious purposes, but because he doesn't want the government knowing everything about him). There's people like me who don't put location info in at all, or who do something generic like "PNW."
Also, even if you're an adult, and you think you know someone really well, you can still have things go wrong with meeting people online. I have met quite a few internet friends irl, and most of those experiences were good experiences. I had one really bad one though, that has caused me to be very careful with people I've met ever since then.
People think catfishing and wasting time in a bogus relationship or whatever is the worst that could happen, but that's like a 2nd to best case scenario. People respond to sales ads with intent to go to your house, see what you have, and rob you later. People lure kids, and adults into bad situations and kidnap or assault them. Any kind of preteen or teen chat app is gonna be like minimum of 15 % dirty old man pedophiles. In this day when kids have moved on to new things, better apps etc, there's probably whole forums, reddits, and chats full of these guys talking to each other, everyone catfishing thinking they're the smartest one in the room.
Let's say out of nowhere your great aunt starts liking your pics and videos etc, there's a good chance some creep at their office saw their pw stuck to their monitor with a post it, (seriously super common) and since this great aunt so and so uses the same pw for everything, and has all their links saved, this guy or anyone else could be flipping thru your photos pretending to be a relative right from the office. Even when you think someone is safe, maybe they were safe yesterday, but today it's really the gross night security guard at their workplace.