Of course, information out of China isn’t that reliable, you could argue. The EU as a whole is considerably bigger than the US, and every year or so there’s a mass shooting or other mass killing. And it’s huge news for a long time. The UK has about a fifth as many people as the US, and this century has had five mass killings (one of which involved guns). The US rate and attitude really is abnormal.

Edit: It’s also worth noting that the vast majority of European mass killing incidents are terroristic; the “someone just shoots a bunch of people for no particularly discernible reason” thing is really, really rare. The Texas shooting (terroristic) would be extremely shocking in any European country and would dominate the news for a long time. But the Ohio one (looks non-terroristic) would probably have an even bigger impact and would likely lead to tightening of gun laws etc (the Dunblane massacre lead to the banning of almost all handguns in the UK, for instance).