"Roland Perry" wrote

At most UK universities, professors are commonly given an Emeritus title
when they retire...

Yes, there are many around, but how automatic is it.

nb. To be a UK Professor requires one to be in effect head of a
department, the USA-ians apply the term much more widely I think.

Not so for the UK now - check Imperial College Physics Department for
example and indeed in 1968 York Physics Department had two.

Of course if you have handfuls of FRS and Nobel prize winners, not giving
them all the title is hardly likely.

The Americans would say (Full Professor) and we used to say Professor (and
Head of Department).

--
Mike D