In as much as we evolved from omnivores, and in as much as all souls
are eternal (so killing animals is not an ethical problem), I see no
reason to be vegan, other than to reduce one's sexual lust. And,
personally, I have no desire to reduce my sexual lust.

By being a vegan, you miss out on the best proteins (whey) and the
best fats (fish oil).

No. I won't help you be a vegan, or a healthier vegan.