Every food commercial, advertisement, and packaging in the US is currently protein obsessed. I just bought 3 burritos, and the most noticeable thing on the entire package is its protein content. TV commercials about waffles are advertising that they have X amount of protein per serving. The products in my jobsite's vending machine have protein all over every package.
You don't have to look far to find the far right's obsession with testosterone (read: gender affirming care for cis men), whether it's giving it to the military or Elon Musk's weird cybertruck shaped body. Then look at who else is pushing that shit nonstop.
Though I did learn there's a weak study that they like to cite, described by Vice here. Emphasis on weak