XDelusion, I think you'd be equipped to put your argument a lot better if you were in possession of the relevant facts.
Such as - OS4 was originally intended to run largely under 68k emulation, but when it was seen to be unacceptable performance-wise, Hyperion started writing the code and compiling as PPC native.
Having a graphics driver running in emulation is going to suck royally for emulation. For something really basic like my WinUAE setup it might work well enough, but my PC's spec would probably outrun the best of the G4 series by at least 150%. Then there needs to be "room" for other applications, applications which want to use a powerful processor for what its worth.
Also, OS3.1 and previous were written to directly hit the hardware. This means assembly code, and probably custom-written compilers to directly hit the chipsets. If Windows' or any other GUI was designed for a single graphics chipset and no other, they would fly. That is something we have to trade in now to get advantages such as upgrading to decent graphics cards, because no-one is going to fund an Amiga hardware startup to produce the latest and greatest hardware, because it would probably cost billions.
If you think OS4 is just eye candy, I suggest you read the featureset documents available at os.amiga.com. I also suggest you read past news articles on it, and I think you'll realise that 'under the trunk' it is very different and much more capable than predecessors.