We live in Czechia and my SO is teacher in local school. She asked a 6th grade girl what she wants to draw today and she literally responded "IDK". It's kind off weird how internet slang is slowly merging in everyday IRL vocabulary.
When I was younger, there were people who would actually say lol. I wouldn't say it's new, but I think the advent of the internet has certainly accelerated some aspects of linguistic evolution.
It would be fascinating to be a fly on the wall in a couple hundred years' time to see where English goes from here.
Yeah, we say lol to each other as a joke when something is "funny" or as a joke in it self, but never as a response to someone outside the family circle or in formal setting. Bot that may change too in the future.
The internet is for sure speeding things up. I wonder how will our (Czech) language look like in 10, 20, 30 years. I am all for simplification but sometimes it just feels weird :D