Technically, yes, and in a survival situation, sure. But when you can get whatever you want at a grocery store / restaurant, it's a much bigger hurdle for people to make that change. Realistically, people are going to eat what they like.

I'd have never even bothered with the plant-based "meats" had the doctor not told me, flat out, "Unless you change your diet, you are going to die". Literally took those words before I was able to force myself to change my eating habits.

Pushing cold-turkey veganism isn't really helping the cause here. Yes, that would be ideal, but it's letting perfect be the enemy of good.

The extra insulin I would have to take as a T1 diabetic to cover a carb-heavy diet would quickly outweigh any financial savings eating beans and rice would.

There are dozens of us out there who have restrictive diets that, while veg* diets are technically possible, are not easy, financially sound, or realistic. I try to stick to a primarily vegetarian diet, but I also recognize that protein is an outsized portion of my diet compared to most people. To accomplish that, animal products are important to me. Cheese, eggs, and even the occasional meat product are going to be things I eat, and not feel bad about.