Have a Scotch to refresh your palate ;-).
Honestly, I was unable to find anything positive about the culture, even though the author thought it was great. The headhunters in Borneo and New Guinea are more sympathetic! If nothing’s left in a few years but the language analysis Mr. Everett did, no great loss; the people will be better off as semi-assimilated Brazilian riberenos.
And they have decorative penis sheaths! That's always a plus.
As in "The heathen riberenos shot arrows at my Sea-Doo as I sped past their dilapidated village, ignoring their poorly constructed "NO WAKE" sign".