Only?

I came across this introduction to an article by Christopher Hitchens in The Atlantic:

Edward Upward was one of the only writers of the ’30s to deal with Britain’s elephant in the room—fascism—but his career was forever warped by his communism.

I have no way of telling whether that’s true – George Orwell was another, perhaps? – but what strikes me is the use of the phrase “one of the only”. I know this is common usage (over 3 million hits in Google!) and I’m sure I use it all the time, but when you come to think of it how can something or someone be at one at the same time time “one of” and “only”? I “only” ask because I am “one of” those who wants to know! Without being pedantic, I think we should say “one of the few” or “one of the rare”.

I’ll shut up now.

Actually, I won’t just yet as I wanted to add a witticism by Oscar Wilde which I’ve never heard before:

On his death bed, he summoned up the energy to mutter: "Either those curtains go or I do".