I was curious, so i googled. I could find a mention that this quote could never be positively connected to Carlin even though (speciallu on facebook) people shared this quote. It most.likely is a wrong one.

https://correctiv.org/faktencheck/2021/11/29/keine-belege-fuer-angebliches-george-carlin-zitat-ueber-dumme-menschen-in-grossen-gruppen/

Well, that’s plain ignorant. But you do you.