>Disappointingly enough, the Marines only just adopted the M855A1 in 2018, and the USAF has no intention to do so.

To be fair, the USAF doesn't do any ground combat with small arms that I'm aware of. Most likely, the only thing they do with that cartridge in deployment is to give it to their security forces, who are basically just guards and almost never use their weapons in combat these days. I'd be a lot more worried about what the USAF uses in much larger rounds, which they fire from aircraft.

USAF Combat Controllers, Pararescue (PJs), and others are elite troops. In fact, the requirements for Combat Controller are extremely mentally and physically demanding. They are not only Air traffic Controllers, which is tough enough, but they are also effectively equivalent to Army Rangers.

USAF has a "Special Tactics" force, similar to the USN's SEALs.

It seems I’m only half behind on my knowledge then.