After a restart, the system performed some updates and then hung late into the boot process. After waiting about five minutes, I restarted and tried again, and now I am unable to even alt tab from the Plymouth boot screen, so I am unable to even view what is taking place
There was, but only that it was updating it. Took north of 3 minutes or so, got past it, and was talking about GDM and delaying exiting Plymouth or something to that effect when it just never progressed further
The most esoteric packages I tried to install to OSTree were things like Dropbear (which was redundant given the toggle in Gnome settings), Neovim, and Fortune-mod.