I saw "Beef is a class 2A carcinogen" and suspect you just watched "What the health"? If so there are claims that that movie got a few things wrong. https://sciencebasedmedicine.org/what-the-health-a-movie-wit...

Also class 2A carcinogens are simply a class of things that probably increases your chance of cancer. That doesn't mean it gives you a huge chance of cancer most of the time the increased risk is trivial.

To give some context red meat is on the same list as:

  Hairdresser or barber (occupational exposure as a)

  Shift work that involves circadian disruption

  Very hot beverages (more than 65℃)

  High-temperature frying, emissions from

  Household combustion of biomass fuel (primarily wood), indoor emissions from

Source https://en.wikipedia.org/wiki/List_of_IARC_Group_2A_carcinog...

"On the other hand, any form of protein is likely to be effective, it concludes, not merely high-protein shakes and supplements. Beef, chicken, yogurt and even protein from peas or quinoa could help us to build larger and stronger muscles."

That's really the part you took issue with? That's a list of protein examples, not "it's first source of protein." It even says "any form of protein is likely to be effective."

Fake HN outrage?

It goes on to say "On the other hand and conveniently, any type of and time for protein was fine. The gains were similar if people downed their protein immediately after a workout or in the hours earlier or later, and it made no difference if the protein was solid or liquid, soy, beef, vegan or any other."

Was your OP outraged?