I think it's UX that commonly works differently in consumer software vs pro software. I think parent is talking about professional software.

Pro software made for speed and efficiency, you usually want to be able to do things quickly, even if sometimes people not used to the software might screw up. Holding right-click, selecting menu item and releasing I think is one of those things.

In consumer software, users would be confused because maybe they long-press the right-click, drag the mouse a little while holding down then releasing, and the menu would just appear and disappear. Confusing UX for most users, I bet.