The intervention if done soely for cosmetic purposes and the dog is not to be bred is fine IMO. No one wants to show a dog with one ear up and one ear down.
If a breeder or purchaser of a dog to be potentially used for breeding intervenes with the development of the dog such as the things listed above, then they are hiding the true fault of the dog.
There are things that can happen like an ear breaking in a fight, or sitting in a crate for too long etc. That would be fine to fix because its an external source that causes such.
But for a breeder to change the development of their dog to hide a fault their line passed down is just ridiculous in my opinion. Know what you breed and avoid it in the future.
"For the animal shall not be measured by man. In a world older and more complete than ours they move finished and complete, gifted with extensions of the senses we have lost or never attained, living by voices we shall never hear."