[bookwormAT]

That many phone manufactures don't update their software is not an Android problem. Would Lenovo update their devices more often when their operating system was not based on Android? Would Apple update less often when iOS was based on Android?

Lenovo, Samsung, Apple and Google are all in complete control of the devices they sell: they all control hardware, software and services themselves.

If the software is based on Android or not has nothing to do with how often these devices get updates.