It's got a lot to do with damage modelling, too, which, currently in AH only calculates the amount of damage in "Hit Point" style.
When total damage accumulated goes over the 'hit point' the designated part will be "totally destroyed" - hence, the term "all or nothing". This sort of damage modelling shows more serious problems in GV fights - one such instance being M16 with four .50 guns raking across the surface of the PanzerIV and knocking out every existing 'damageable' part there is.
There is a lot more than this when a plane is supposed to receive damage. For example, the "quality of the hit" - when a .50 round hits, it could be a 'grazing' hit, giving off minor shock but doing not much other than grazing the paint job. Or, a hit from direct 6Oc angle has a higher chance of being 'non-lethal', than a hit from other angles.
I know some people are getting annoyed about IL-2 discussed here, but the truth is, IL-2 DM models a lot more factors when a plane is to receive damage. I've seen the difference between a case of 'empty burst' and a 'direct hit' from a cannon round in IL-2.
For instance, a cannon fired from direct 6Oc angle has a lower probability of getting a good hit in, since the target shows minimum area in that angle. The results are, some cannon shells strike near the surface of the air frame, which shows off 'explosions', but the damage when you see it, is not very serious.
You could see five to ten such explosions and the enemy plane does not go down. On the other hand, a 'direct hit' which digs inside the structure and blows the chemical charge inside the airframe results in huge damage, big holes are soon visible, and the level of damage is totally different than a 'empty burst'. Same thing happens with big cannons such as 30mms. A grazing hit bursts large, but only small holes are visible. A direct hit usually knocks out a wing or a fuselage area in totality.
....
IMO, the largest disadvantage from the 'all-or-nothing' DM is to the planes that were known for 'rigidness'. 5 cannon hits indicated in AH are all the same in damage, while 5 cannon hits indicated in IL-2 all differe in quality. The chances of every hit being a lethal one is 100% in AH, but it differs with each hit in IL-2. As a result, tough planes such as the IL-2 last incredible long, living up to its reputation and boasts amazing structural integrity in withstanding enemy attacks. In AH, the IL-2 simply has a bit higher hit point than other planes, but when all 37mms and .50 AA fired from GVs hit with 100% damage capability, it rarely means anything. Same with 'rigid' planes like the P-47. Two~three hits from a Hispano will dismember the wings easily.
Unless some more factors are put into AH DM and gunnery - such as 'quality of the hit', 'probability of giving out a lethal hit', 'accuracy of gunnery diminishing with distance(300~500 yard hits)', planes like the "IL-2" will continue to be a wall flower in the MA prom.