It's the first solid thing our kid ate, and he loved them. I guess it also depends on when they are exposed to that. If they are 5 years old, it's probably too late.
Taste also evolves. My daughter loved broccoli (and a bunch of other things) when she was little, but once she turned 8 or so her tastes completely changed.
Yup. I favour Mornay Sauce (a.k.a. cheese sauce). I have no idea why hating broccoli is a meme; broccoli-cheese with french fries is a nutritious and tasty meal.
As an adult: it's bland by itself, needs sauce, or at least black pepper and olive oil.