Anthropologists don’t have a good track record getting the streight poop on this topic from “native” people.
On the other hand, these particular anthropologists don't seem to be pursuing the "primitive people are polymorphously perverse like the peaceful loving bonobos" line. And it should be more-or-less verifiable as to whether they have words for homosexuality and masturbation in their vocabularies. Reportedly, they don't.
“Anthropologists dont have a good track record getting the streight poop on this topic from native people.”
Yes, or reporting unbiased results.