you’re forgetting time for cleanup, assembly, put everything back, move shit out of the way, precut veg into pieces which fit in the machine.. etc etc.
Specialized equipment in a kitchen is all about the time trade offs.
I absolutely loath cutting julienne carrots in a kitchen and the robot croupe is great at that for sure. Potatoes, too. But some things wouldn’t save a lot of time really, like slicing cucumbers which would be faster to do with a knife and cutting board.