I could comment on what sort of "meat" he likes to eat ...
but I'll just say that picky eating is not a good survival trait.
I am a very picky eater too. Unlike this stranger, I like seafood (except oysters, yech).
Many years ago, at least forty years, I got tired of my self-proclaimed betters saying you need to eat ____________(fill in the blank) because vitamins and minerals, bla, bla, bla...
I bought "Earl Mendel's Vitamin Bible", read it from cover to cover and have referred back to it many times. I take 21 pills, tablets or capsules of supplements every day, including the the ones that my doctors have recommended I take like fish oil and D-3.
I do eat lettuce, potatoes, carrots and pinto beans (no other bean or pea, well, except maybe a great northern if I'm in the mood).
I, to this day resent the persecution I suffered as a child at school and at home because I didn't "clean my plate." In first grade, I was made to sit by myself with my tray in front of me, in the school cafeteria until the end of school hours, because I didn't eat my English peas. I was spanked because I vomited up food I was forced to eat, or spanked because wouldn't eat something I was told I would like, but I knew better. Accusations that I only did it for attention. Constantly did without because I was given a hamburger with onions on it. Or doing without any food at all when everything on the table had inedible things in it. Mackerel fish patties never needed onions in them. Being a picky eater is a real thing.
It's also not a good survival trait.
It just isn't. When food is scarce, and vitamin pills nonexistent, being a picky eater means starving to death. I hope you're grateful that you live in a First World country with (still) a more or less free economy, in which being a picky eater DOESN'T mean starving to death.