I understand what you are saying. I'm saying that doing this properly is a solved problem, and that power consumption isn't an issue because many of the feature

I understand what you are saying. I'm saying that doing this properly is a solved problem, and that power consumption isn't an issue because many of the features they do have (not AGC or frequency/amplitude compression, those are quite simple) would consume far more power than it would take to do this properly. Modern low-power DSPs can achieve latencies in the microseconds, especially for such a simple task as EQ. That's going to be far beyond human hearing to notice.