That's not really how any of this works.

Pulseaudio is both a protocol and also an implementation of that protocol. Pipewire also implements the pulseaudio protocol, hence its compatibility with all existing software.

Wayland is a protocol only. Every compositor - and there are many - implements it "from scratch". The "pipewire of display" would simply be yet another Wayland compositor. No one is going to solve the problems of Wayland in one fell swoop by releasing another Wayland compositor. What is actually happening is that problems are being gradually solved by the introduction of protocol extensions, which usually get adopted by other compositors after achieving success in one.