Got your point but that's really a matter semantics then...
The output image is only the result of many, many approximations that generally try to simulate the real life. If you push your logic to the end, anything that isn't real isn't adequate. Or any cel shaded game shouldn't be allowed to exist because they fail at being truly hand drawn...
There is no "same output", only an image defined by a series of parameters, sometimes forced, sometime tweakable. There is no holy grail of IQ, just choices and tradeoffs. AA is one, so is resolution, framerate, texture used, models polycount... You don't start with a perfect picture that you then modify in good or bad ways. You build something from scratch and try to do the best you can in the fastest way possible.
To me, anything that make the process quicker is an optimization. Worthy or not, that's personal judgment, subjectivity.