This is kind of an old discussion. I'm perfectly happy eating meat but equally recognise that vegan diets are perfectly feasible for almost everyone. If not vegan, then vegetarian (preferably with a premium on animal products to reflect their impact etc).

A nice example of this is omega 3 and similar: it is actually synthesised in kelp and works its way through the food chain to us with fish as an intermediary. It doesn't have to be that way, it just is right now. B vitamins are a similar story.

"Animal products" yes (with the caveat we're getting good at genetic engineering and also vat-growing meat cells); "flesh" no; "poke their eyes out and boil them alive" absolutely not.

Can you elaborate on how I and a good number of the people I know cannot remain healthy? I have to say, I feel pretty fine.

Which nutrients that we need to eat are only found in animal products?

Whichever nutrient is required for smug satisfaction of beating nature at its own game and being so far beyond the food chain that it might as well not be a thing.