The non-vegan lifestyle

It was actually mostly meat that improved our brains. Sure, some nuts, berries, roots and other things were involved, but vegan and vegetarian lifestyles are only possible for large numbers of people thanks to modern technology. Sure, there may have been some people in the past that partook in those lifestyles, but they were few and far between.

Specifically cooked meat with more caloric content.

High quality animal products probably means meats with no antibiotics, msg, or hormones. Also free range eggs and organic milk and dairy Products.

Makes no difference since no-one's seeing the tweet from behind the screen, stop being difficult

Like mildly difficult or Doom difficult? And is there a way to see behind the screen?

Yes, but not without voiding your warranty.