Is it possible to get the reverse of this working? (Waydroid with play services on Linux phones, such as postmarketOS)

This can probably be upstreamed into podman. Podman already has supports using a VM using podman machine (uses different tech under the hood depending on the OS). This seems like it can be yet another backend for it.

I just want a folding portable monitor now. We're getting so close...

curious is this just software qemu(not sure what word exactly was) instead of virtualization acceleration, probably more overheads?

And local FS access is mediated how?

With this I could in theory do all my work from my Android phone.