[j.p.s]

Originally Posted by Quoth

Was it Oscar Wilde?

A search suggests not and also a theory that it was someone jealous of people that could invent puns!
https://quoteinvestigator.com/2024/01/04/pun-first/

It is the sort of comment he might have made.

I've got no idea, but it rings a bell. And maybe he also said wit instead of humor, like everyone else.

I thought the custom of some people groaning at puns goes way way back.

I'm not adept at generating puns and many of those I come across go right past me, but sometimes I get a laugh and I have nothing against them. I don't remember hearing of the jealousy explanation, but it seems plausible.