I would not say I rant about it but I see quite a lot of careless errors in Trees. Durham, North Carolina for instance in a tree when the people have lived and died in County Durham, England.
I used the "rant" word from your thread title!

As I have said many times, on several threads, that is the fault of the tree owners who don't put a country name after the town name!
Ancestry, being a US company, defaults to the nearest equivalent American town (or county!).
Yes, I think Ancestry care wrong, and the default from a .co.uk search should be the UK name (ditto for Australia, Canada, or wherever!).
But essentially, it is user error. After all, how hard is it to select the correct town from the drop-down list, or to simply enter "England" after the town or county name?