They can be great - in the right hands.
I’ve had plain cabbage prepared by native Chinese visitors that was EXCELLENT.
I had an American buddy cook zucchini that was SUPERB.
Most of the time that stuff goes straight into my garbage can or compost pile. I very nearly threw up at the dinner table over zucchini my mother made.
But these two instances proved to me the problem was in how it was prepared.
Now if somebody can make turnips, rutabagas, and others tasty, I’ll put down the meat to take a few bites.
Peel a turnip and eat it raw. It is kind of sweet and crispy, much better than cooked.