Some people still run Workbench on AGA, so they would benefit from the increased speed of PPC.
Bottleneck on those machines is not CPU but AGA. You get awesome boost if you dont use slow AGA at all but render gfx on the PPC instead.
That is, AGA is equally slow on 68020 and PPC but gfx on BVision runs faster on PPC than on any 68k.
