Judging people based on age

I don't really use spacehey much but I like complaining so who cares
So I see a lot of people online saying "Omg these 13 year old kids shouldn't be on the internet, they're too young!' As if these people who're barely even five years older than them weren't doing the exact same shit when they were our age, and yes I understand that sometimes some people of some ages shouldn't be on certain sites and shit but that's like a ten year old on twitter or an 8 year old on anything except Youtube. Ultimately, it's not any different from the insta and twitter 13 year olds of 2014. OKAY?
Just let people have fun, instead of telling people not to go on sites where they might see harmful shit, maybe oh I don't know... STOP POSTING HARMFUL SHIT ONLINE! Simple.
The same goes for the other end of the spectrum, older people around 35-50+ using social media other than facebook. Again, these people are just trying to have fun by sharing their thoughts and opinions. Those of which aren't telling others to get off the platform or you're a worthless sack of shit just because you didn't grow up the same way as them. Let the 13 year olds, at least the ones who have brains and know not to do dumb shit, and the middle aged people, who aren't bigotted dicks, have fun by watching dumb stuff online and talking to their friends.