Not quite. Say you are flying on OZ metal on a flight which also happens to be a UA code share (e.g. ICN-SFO). Now if you are a UA Mileage Plus member (Premier Executive or above), you would get 100% bonus miles with a UA flight number, but only the regular miles if you flew on a OZ number.

Ergo, code shares on *A do play an important role, contrary to popular opinion on this thread.