Heart disease is the #1 cause of death in America... you don't think that meat (especially processed meat like cold cuts) is not part of the problem?
Truth is, the way we produce meat right now is not sustainable. We will eventually have to reduce our meat intake, and I wouldn't be surprised in let's say, 50 years, we drastically reduce our meat intake and meat might even be banned. They will probably look back and think how ridiculous it was that we ate so much meat and how fucked up the meat industry is. It's just culturally accepted right now so no one gives a fuck about it. Remember how slavery was "normal" and no one bat an eye back then? Similar phenomenon with how the meat industry treats animals right now.
There's no reason not to go vegan other than "muh bacon" or "I like the taste of it". Those are pretty much the only valid reasons I can think of.
http://www.ncbi.nlm.nih.gov/pubmed/19562864
You simply don't require animal products to be healthy at any stage of life or to perform as an athlete. Yes, that even includes those who lift weights like I do and want higher protein, vegan diets work just fine. There are plenty of jacked vegans out there. In fact, vegans are healthier on average, and meat is associated with heart disease and classified as a carcinogen by WHO. It's just the diet that makes the most sense, it's just a matter of time before it becomes mainstream.