Agreed. If the controller answers with the wrong type I usually, in the immortal words of Sam Goldwyn, let it roll off my back like a duck. I'll just enunciate better in my next transmission.
But where it can make a difference is if the controller answers me as, for example, "Stationair 7YQ" (instead of Skyhawk), then proceeds to tell another nearby airplane that he has "traffic at three o'clock and two miles, a Stationair" ... That's when I'll jump in and correct him.
On the other hand, you can't always assume that the controller is wrong. More than once I've heard my abbreviated callsign with a different type, and there really was another airplane on frequency with the same abbreviated callsign. If there's any doubt at all, I'll ask, "Was that for Skyhawk 7YQ?"