I don't think everyone should be vegan. There are plenty of reasons why someone would be harmed more by a vegan diet. But, the vast majority of people would see health improvements by switching to a vegetarian or vegan diet. And you can still be a bodybuilder with a vegan diet. That's all. If your doctor says you can't be vegan, don't. If you can't afford vegan food, don't. If you don't want to be vegan, well, at least try to eat less meat. Baby steps.