For me, it's chicken all the way. I've always loved chicken nuggets and rotisserie chicken, though I much prefer eating boneless chicken because it's easier to chew. Beef can sometimes taste bad when not cooked well and generally speaking chicken isn't as smelly as beef can be.
While there are some chicken dishes I prefer over beef (mainly chicken strips/nuggets, lol), overall I'd have to go with beef over chicken. I just find it more appetizing.
I voted both because I enjoy both from time to time, but I definitely eat more birds than mammals. I actually eat turkey more often than anything else, which people generally find unusual.
Chicken has always been my favourite meat, enjoy chicken nuggets, roast chicken, chicken tikka etc - find it versatile and easy to eat.
I used to have beef when I was younger but stopped eating it (and generally most red meats) a few years back due to a slow stomach so find them very hard to digest, I don’t actually miss beef though so it works out.