After day 1, if you are the winner, no need of 12 AMRAAM per plane!
And, between you and me, how many AA missiles have been fired in a war situation since Vietnam ? 2? 3? never 12 or +/- 20 like the F15X. once again, marketing only.
Most A2A kills in Vietnam and post-Vietnam were done by A2A missiles. Of Vietnam war era A2A missile were not bery accurste and temperemental and yet still killed more enemy planes in A2A combat than cannons.
We're way past gunfights in A2A.