I disagree with this 100%
Nintendo gets away with less RAM because they've been behind in graphical output for the last several generations. If this things renders at 720p and just upscales to 1080p no matter what, of course it doesn't need as much ram as a PS4! But I wouldn't spin that as balance, I mean it is because it'd be obscene to throw 8GB of ram into something weaker than a PS4, but it's not really "balance" because in reality it's not that they've found some clever way of doing with 4GB of RAM what their competitors need 8GB to do, they're just not capable of doing what their competitors can do period.
I wanted to object to your iPhone argument regarding how it's different coding in an environment versus the more lower level coding you can do for consoles but I'm not sure that argument's apt anymore. I still think it's a silly argument though, Apple only has to tune their software for a handful of devices, Android runs on everything, so yes, there's some smart engineering and coding going on there, but it's not like Sony and Microsoft have fragmented consoles either, neither would be a good example to relate to Google in that example. Really, all three console makers would be Apple in your scenario.
Regardless, the second it was a hybrid the die was cast, battery life, size and weight all became a clear priority and matching the PS4 and XB1 was pretty much impossible.