The DC-9/MD-80 (especially) and B-727 had tail poles to prevent this, not sure about B-737 and higher (didn't see a place for one to be attached when I was working on a modification of a 737 derivative. More like poor pax loading/unloading process to me.
I wasn't speculating on what might have gone wrong, just repeating what ESPN said.
Per SI, it was a "tail stand".
https://www.si.com/college/2021/09/18/usc-trojans-plane-tipped-backward-sitting-airport-tarmacThe grounds crew for the plane did not put the plane's tail stand in place. After the scary moment, the grounds crew leveled the plane, allowing the remainder of the passengers to exit. Did you do ground ops in the AF? Based on what you have done for contractors, I would have thought you did maintenence of weapons systems. Of course, depending on how long you were in, you might have done multiple tasks over time.
My BIL did maintainence, though I can't recall what models. I want to say B-52s though. His last assignment was Travis AFB in the early 90s, so whatever was based there at the time.