I used to eat a ton of meat about 10 years ago and before that. Slowly as I get older I found myself eating far less meat and eating more vegetables. Not because of things like above but because I felt better physically doing that.
Fast forward a few years and I got told I was Type-2 diabetic. That scared the crap out of me because I hadn't hit 40 yet.
I jumped on a no carb, Keto diet with mainly vegetables, high sources of good fats and limited protein mostly chicken & fish (pasture raised / wild caught) and grass fed beef when I do have it. I have lost a ton of weight, not needed medication for blood sugar, have heap loads of energy and feel the best I have ever been.
I think diet has a lot to do with it and meat isn't evil but I think quality meat is the answer in moderation combined with an abundance of high fiber vegetables.