Dang, some of y'all damn near brainwashed by the meat and dairy industries.
If you're already an adult man it's not even difficult to get enough protein in your diet to get any kind of physique you want.
Nuts
seeds
lentils
beans
soy
wheat protein
other high-protein grains
nutritional yeast
mushrooms
Lets say you need 150-200 grams of protein a day to be an average-sized person with a bodybuilder physique. Almonds are almost 100g of protein a pound. Peanuts are 120g of protein a pound. Tofu is 40g of protein a pound. Lentils are 40g of protein per pound. Chickpeas are 80g of protein per pound. Wheat flour is 50g of protein a pound. Plus you're gonna get 5-10g of protein in every cup of high-protein veggies that you eat (peas, sprouts, spinach, etc.).
If on a typical day you eat about 8 ounces of nuts and seeds of various kinds, 16 ounces of beans or lentils or soy, 16 ounces of whole-protein grain, and then mix a smattering of nutritional yeast/mushrooms/mycoprotein/high protein veggies, you can get to 200 grams of protein without doing anything crazy. And from time to time replace some of that with a little bit of fish or lean chicken so you don't get bored.
That's all for a bodybuilder. The average person who is just looking for a lean physique can get by on half as much protein easily.
In fact, attaining a nice physique on that diet is EASIER because the main reason he looks good is cause he cutting fat and fatty meats and dairy are two of the biggest sources of fat in adult men. The fact that some of y'all are talking like this is some kind of scientific impossibility is just silly.