You're probably talking about a famous/infamous interview from Hayao Miyazaki, which includes him saying:

“If you don’t spend time watching real people, you can’t do this, because you’ve never seen it.”

“Some people spend their lives interested only in themselves.”

“Almost all Japanese animation is produced with hardly any basis taken from observing real people, you know.”

“It’s produced by humans who can’t stand looking at other humans.”

“And that’s why the industry is full of otaku!”

"It's produced by humans who can't stand looking at other humans" is the best encapsulation of the issue, imo