And by Apple leaving it like it is (and has been for 8 iterations), they would find many all for it. No need to "fix" what isn't broken.
BTW, I've been using an HTC Desire (610) and a Moto Droid 3 to test an app that we are working on for both iOS and Android. After about a week, I still find the inconsistencies in button design across the Android devices confusing. So in that regard, I'm still looking to see what Android does better. From where I sit, that's not snarky, it's simply fact.
Just because Android hardware manufacturers took a decent idea and screwed it up across device iterations doesn't Apple would make the same mistake. Apple prides itself on style after all. If they adopted a 3 button config, I'm sure its design/execution would be the same across their whole line up.