It seems to me that being able to use compose navigation without having nested nav hosts and nav controllers you will end up having to build a handle every edge case type setup, but not just for bottom nav, also the toolbar, drawer, fab setups.
Or not sharing a scaffold and you pay the performance hit of a full recomp for every navigation event.
right now I am leaning toward building some way to nest navHosts and navControllers but hopefully in a form that allows me to retain deep linking without a headache.