Earlier quoted context omitted.
I have iOS 7.0.3 on my iPhone 4S. Released a month before the Galaxy Nexus.
Have you gotten all the features, the iPhone 5S got? Do you have the nice blurred Control Center background? Android's Problem is fragmentation, and it wouldn't help at all to just backport some functions to older devices, because then developers coulnd't be sure about tthe availability of any API.
Contrast that with Android, where developers are still targeting Gingerbread and are unable to take advantage of any of the bug fixes in ICS, JB or KK.