@OK465
If i remember correctly it was removed in 2012 or early 2013, but i can't really recall the date.
Haven't been lucky enough to fly aircraft with the AoA gauge which seems to be indicated where some have the round dial RA display, there is an alternate purely digital RA display location on the bottom of the ADI part of the PFD. We have both RA displays in our fleet. The AoA display is available on the 737NG, 764, 777 and probably 787 and 748.
I did understand the same as you that it displays unfactored AoA, however with a red tick for stall AoA which is dependent on mach number. Boeing published a nice article about it in their
aero magazine.
Wouldn't have helped in the majority of our unreliable airspeed cases as those were caused by frozen AoA vanes. Interestingly enough that resulted in wrong indications of airspeed, altitude, ground speed and wind info on the affected side. Luckily there was always only one sided affected and the ISFD doesn't take any AoA input and displayed correct information as well which made the crosscheck easier.