Maybe, but it's the balance of what you can do rather than any individual item on a specification, particularly when you're comparing devices with other different hardware elements running different operating systems.
Plus developers have got the increased power of the 64-bit A7 and the features of the M7 chip to keep themselves entertained so it's not as if Apple are treading water.
Besides do we really want to recreate the "requires a minimum of X Gb RAM to run" small print world of Windows games?
If Apple doesn't let its apps get more intricated, competitors will do it first...