I hadn't heard that. Knowing of some of the horrific attacks that have been made on human carers by so-called 'tame' Chimpanzees in the USA, she could have been right. Whereas the keeper sitting next to the female(?) Gorilla I would say is 100% safe.
I've been flicking through 'Molly's Zoo' where she said: "We always encourage our keepers to become attached to their animals, and treat them as their own..." Leading by example!
I remember as a small child seeing Molly driving round the zoo in her car. As the car approached the chimps (I think) the whole troop suddenly woke up and began running around and calling ever so loudy. She stopped the car and got out and then all the chimps basically lined up for and waiting for some treats which were thrown into the enclosure!