Earlier quoted context omitted.
Container is a chroot jail on steroids. VM is a QEMU process (also in a container).
how can you run a totally different architecture from just a chroot jail? It doesn't make sense. How are you "on the metal" if you're running some totally different kernel from what the chroot-jail-host is running? You can't both be running the kernel on the metal...
The containers don't run a different kernel. They're just regular processes, in an fancy evolution of a chroot jail.
If you want to run something like Windows or FreeBSD, then you break out QEMU.