I read a detailed account of the Miami shootout by Ayoob.
The FBI learned a few things but also made an incorrect judgement regarding the 9mm.
The fact that the FBI agents were under armed was true. Mini-14s vs pistols is just not a fair fight. Even the shotguns were not their equal at first.
A big part of the problem is the bad guys just would not go down even when they were basically dead. The 9mms had performed properly including tearing the aorta off one guy who incredibly kept going for almost a minute.
Were they semi auto Mini-14s or AC-556 (full auto Mini 14)
One of the agents who was killed, used multiple reloads and fired 29 shots from his service weapon. He never hit either of the assailants.
Two other agents lost their primary weapons as they came screeching to a stop at the scene. The weapons were stored loose on the passenger seats and bounced out of reach.
Clouds of road dust raised from the stopped cars made it almost impossible to see in the first minute of the incident.
The caliber of ammunition used was largely irrelevant.