A good benefit to calculating the perspective math on the CPU is that it allows one to execute some neat tricks. Like with this PerspectiveViewportContainer2D I've made, which allows a user's input to propagate into a child SubViewport. This mimics #Godot 's regular SubViewportContainer.
Made a "PerspectiveCarousel2D" node that drives the X blending, as well as a "CarouselAnchor2D" node for non-PerspectiveQuad2Ds. While there are clear limitations to this approach, I could definitely see this psuedo-3D rendering being useful for point-&-click style #Godot games.