The problem with Android has always been the hardware integration. The sleep problem is just one symptom of a larger integration problem that spans across media standards, availability of hardware features, subpar drivers etc.

Android still suffers from many apps being designed to work on background (which works on pure Android on the emulator), but being killed depending on the manufacturer running the OS, which require tech savvy users to fix them by tweaking obscure configurations.

Android is what happens when you have a technical engineer idealizing features instead of a product person thinking about the end user first. All the problems from Android seems to be a lack of effort to standardize things or to think how that feature will impact users experience of that product.

The fact most manufactures just care about selling the device and not support it after creates a perverse incentive to fool users with bad features as long as they look good on ads.