If drywall is patched, shouldn't it look flat like it never needed repair?

In my new house there is a section of the ceiling about 8 inches by 48 inches that looks obviously patched. It is a perfect rectangle. The ceiling has knockdown finish, which will never be perfectly matched I understand that, but to me it looks like the drywall patch is thicker than the otherwise existing ceiling. The superintendent is saying the patch can never be perfect and what I am noticing is the knockdown, but I say no, because I can see the wear the rectangle of drywall was replaced. He agrees they did have to patch the area.

Why would a drywall new seam or new piece be any different than any other drywall seams that are all over the house when installing drywall?