Qubes uses VMs, Jails use a shared kernel. So I wouldn’t say Jails are safer nor that they have a smaller exposed area with regard to host isolation than VMs.

Qubes can be viewed as a Xen distribution, rather than a Linux distribution [1]. You may find the Qubes FAQ a good starting point (I'm reading it now because of your question, so thanks).

[1] https://doc.qubes-os.org/en/latest/introduction/faq.html#is-...