That's not the reason. The host android has full access to the child VMs; the VM can't hide anything from the hypervisor. It's about isolation. The child VM can't leak your photos or contact list if it doesn't have it in the first place, and sticking things into their own VM provides an additional layer of isolation beyond what exists currently.

I don't think that's true; my recollection, which appears to match https://source.android.com/docs/core/virtualization/architec... , is that Android uses hardware support to run VMs that even the host kernel can't actually see into.

fascinating link, thank you!

The host android won't have access to the guest VMs but the hypervisor still does.