Yeah, there's enough posted on the open web that one might, if unfortunate, encounter it. I've seen it randomly put up on FB once, by some spam account.
Then there was this creep running for office in Virginia on a platform of enslaving women and getting rid of age of consent laws... I unwisely went to his campaign site to see just how nuts he was, and the guy actually posted CP on there, with a "If elected, I'll legalize THIS" rant underneath. It was pretty appalling. He was promptly thrown out of the Libertarian party, and soon afterward went to prison for exactly what you'd expect... and he thankfully killed himself pretty quickly.
It was relatively recently when I learned how prevalent it is on twitter. What I've learned about CP on the internet is that it's all over the open web, but the platforms it's shared on don't seem to be very interested in cracking down. If the EU wanted to do something about it, they'd light a fire under some asses to regulate their own sites rather than roll out nonsense like this law.
School IT, eh? My SO did that for a long time, too. No shortage of horror stories on that beat, hope you're in a happier position now!