Check is your object's name is typed correctly, or have a space in front of the object's name. it works for me.
Good evening @edmarvis:
Several years after your entry and I'm experiencing this same issue with iOS17.
Only as an extended info on this issue. I see that hosting the "CosmonautSuit_en.reality" example from Apple (https://developer.apple.com/augmented-reality/quick-look/) in my server, that same message "Object requires a newer version of iOS." is shown on screen when I try to access it from a button in my user interface. On iOS16 and below, the access to the AR works as intended.
Please, note that I'm using an Apple's generated (and so perfectly formed) .reality file, so it leads me to think that the problem might be related to something in my hosting server.
Could be something related with "extra" security specification for the hosting server that has been changed on iOS17. I'm saying here "extra" because I have running at the moment a valid SSL/TLS certificate, so I wonder if HSTS would be also necessary.
In parallel, I've noted that the direct access to the .reality file (typing its URL in the address box of Safari) do work, and you can access the AR experience, when clicking the on-the-fly poster generated by Quick Look AR (QLAR). Also, not specifying the rel="ar" attribute in the anchor tag makes the trick, and again after showing the on-the-fly generated poster, you are transported to the AR by clicking it down.
Thanks for your time.