From the post: "Food manufacturers have a financial incentive to replace protein with cheaper forms of calories, and to manipulate the sensory qualities of foods to disguise their lower protein content."

Essentially, the price that people are willing to pay for a food is less sensitive to protein content than it is to flavor and mouthfeel. If you reduce the protein content of your product from 80% to 75%, and replace that with an additional 2.5% sugars and 2.5% fats, people will probably think it tastes better, and they will eat more of it because of that and because the lower protein content (according to the article) does not trigger a satiation response as quickly.

People will pay more and eat more, while your materials cost goes down. What profit-seeking product manager wouldn't make that change between eyeblinks?

The only possible pitfall is losing customers concerned enough about nutrition to determine whether your product still has the best health value per dollar. If you have ignorant consumers or copycat competitors, that's hardly a concern at all.

It depends entirely on the food and the specific process it may have been subjected to. Applying excessive heat to organic compounds can denature them, removing nutritional value, even if it doesn't burn food.

Preservatives might cause certain foods to retain food-like properties and flavor (saltiness, for example), even though the food has aged more than might be superficially apparent.

So, if you have a food that has been cooked at the factory, and then it traverses various temperatures during shipping, ages on a store shelf for months, then gets over-microwaved in a convenience store, and then eaten, it might taste like an all-beef frankfurter, but from a nutritional perspective, it's shoe leather.

That's not the worst thing that could happen to meat though. In general, most people tend to agree that "pink slime" is the worst material that agribusiness is still allowed to call "meat."

https://en.wikipedia.org/wiki/Pink_slime

The poultry counterpart to "Pink Slime" is called "White Slime", since Pink Slime refers to beef. Pink slime is actually a thing, and many of us have probably eaten some of it, somewhere along the line.