I dont' believe it should be mandatory not to crop or dock. I think it should be up to the reputable breeder and or purchaser.
For myself absolutely no I would not own a dobe without being docked, maybe the ears could be left if it was a rescue, but I would want the breeder to dock and crop if I was the buyer of a pup. Just as black dobes are my preference. I would not own a blue or red. Just a personal preference.