https://www.momsteam.com/chronic-traumatic-encephalopathy/cte-media-continues-to-be-ahead-of-science
I'd guess they didn't have a sport as extreme as MMA in mind when they wrote the article.
Nevertheless it’s a well researched article with over a dozen Neuroscientists quoted as opposed to the same one or two sources you see quoted in the New York Times.
From some of the people out there you would think the sloshing around of the brain inside the skull of a seven year old girl on a trampoline doing a backflip would cause a brain disease.
Meanwhile Obesity and not participation in contact sports continues to be the single biggest predictor of brain disease.