Otte: staring into the abyss

You have plenty of "UI diversification" in Windows-based applications with no shortage of bizarre user interfaces for special purpose applications like digital camera image management tools produced by camera vendors. It would be better for the user if any necessary software were integrated into existing frameworks, but that obviously doesn't provide all the fireworks and spectacle that a heavily branded and poorly integrated program has to do to satisfy the product management.

You also have a lot of widely criticised messing around with user interface shells on top of Android, apparently. None of this work gets contributed to Android because the companies involved want to keep the supposed benefits of such work to themselves.