Very true, very few dim sum placed use carts in HK it’s now very much the exception and definitely no good places will use a cart.
Interested in the comment about the temperature difference between carts and off the menu ordering. For me it’s a sign of a bad restaurants if the dishes are not freshly cooked to order and served very very quickly…they should be scalding hot when the arrive at the table…too hot to eat.
I do agree baked can be served slightly cooler but pastry should still be crisp but I would have thought good fried dishes need to be served quickly as well as there is nothing worse than a soggy batter.
