Cats in europe are even worse. You go to certain cities and there are thousands of strays lying on the roads and roofs, populations seemingly sustained by dumpster diving, rats, plus plenty of restaurant owners or workers straight up feed the cats regularly. There are seemingly no catch and fix programs like in the US.
a quick google search tells me that there are 75 million feral cats in the usa, far more than any other country - by area or population or any way you want to measure it
This seems like a number that would never be accurate no matter where you look. Either way, you just don’t see cities coated in cats like you do in Europe. Like dozens and dozens of cats up on a roof is a very common sight when you start exploring especially Mediterranean cities. Cats visiting you multiple times as you sit outside at cafes. Hotel and resort feral cat populations that the workers know by name at this point. I’ve seen it all. There’s just nothing like it in the US. Maybe in Key West at hemingways old home, I’m told.