Speed is not relevant for stalling - wings do not stall at a speed; they stall at an angle. So if AoA is uses it is to give the driver access to the prime information, not as a substitute for airspeed.
If an aeroplane can be landing at a wide variety of weights the stalling *speed* will be variable, but the stalling AoA will always be the same. This is more of an issue for combat aircraft (which may routinely return with unexpended ordnance) than for most civil airliners (which tend to land at more predictable weights in normal circumstances).