Ditto to many of the previous comments. I almost exclusively buy the shanghai baby bok choy these days because I find them tender and versatile for stir fries, quick blanches, etc. I’ve had regular bok choy sliced and stir fried, or really chopped up to be added into other mixtures for texture. I think think cutting up the leaves helps with the chew issue so I haven’t noticed it as much.
I definitely agree the Asian veggies I find in the few Western markets locally tend to be much older and mature plants. It’s one thing if they weren’t turning around quickly, and were just looking sad and withered. They often seemed harvested well past their prime, IMO.