As I'm a dinosaur and worked with the Windows Management Tool long before XOA was around, I know it's always there as a backup for the minimal tasks AND I'm proficient on the command line as well.
The team is working on an onboard solution:
https://xcp-ng.org/docs/management.html#xo-lite
IMHO, I wouldn't dedicate real hardware to a simple task as XOA.
In my setup, I have two pools which are connected on a network level, so I have 1 XOA running on each pool, in case of dire need (which I did a couple weeks ago).