Of course. But it could be a lot simpler, too. For example, USG doesn't have PoE (only the EdgeRouter X does, I think), and the AC itself doesn't have a power adapter. Both things would have made things simpler.
My wish is for a prosumer wireless router that's rock stable. I've burned through numerous routers that all have had weird issues. The closest I've gotten was my Microtik AC Lite, which I loved, but it doesn't have an external antenna, so its range was questionable.
No injector came in the box. I remember reading forum discussions about it at the time that explained which models/packages came with the injector, but I forget what they said.
I've purchased only nano-HDs and AC-lites, and they all came with one in the box. What didn't have any is Cloudkey 2 Plus. I had to get a third-party injector for that one (or Quickcharge USB charger with USB-C cable - I went with injector).