(It's not that males are disposable, it's that as the species level, selection would prefer top ends to reproduce more and the male top end would be significantly smaller than the female top end. This results in a more distinct strategy for the top ends, while a more "normal" strategy mix for the rest. In any case, low end males are very low value, while high end males are very high value - more so than even high value females. As you scale back into tribal periods, it's well worth losing a fair number of males to capture "female resources", even though it isn't as omnipresent (read: dominant strategy) as we hear.)
I see us going through an equalization period now, regardless of how true the above is.