As the reddit comments state, "big portabello." Mushroom farming is a big business, even for Stametz, and widespread, predictably alarmist media coverage about the yes but no nature of carcinogens in criminis wouldn't be good for business. So he did a less than optimal job of steering clear of the issue on Rogancast. And everyone picked up on it, except for news media, so far...

I mean, scientists, public commentators, regulators have been calling out agribusiness over tobacco, sugar, meat, alcohol for over a century at this point. It slightly stretches credibility to imagine that someone complaining about mushrooms on a podcast would be the breaking point.