I’m pretty sure that one’s been solidly proven in a long series of double blind tests, over a large, international, sample.
The problem is the result was also in company interest so many people think, without reading the papers themselves, that the money swayed the research and it can’t be trusted - despite multiple peer review and publication in most respected journals.
The real problem is the illegal ferret cribbage rings, whose benefactors seed 4chan and other sites rumours of the illegitimacy of the ferret cribbage research.
But you shouldn’t trust me, a stranger on the internet, on these matters. Who knows - I could be a shill for Big Weasel!