I've read that on paper the Egyptian Mig 21 in 1967 were virtually equal to IDF/AF Mirage IIICs but EAF pilots couldn't fly them to the very limit, which was equivalent to having a fighter with inferior performance.
Interestingly enough in 1967 Israel only used guns in air to air combat, their shafir 1 was a dog and the R530 was not much better. They only really adopted AAMs in 1969 with the Aim9D sidewinder. Also keep in mind that the IDF/AF used the F4 as a strike aircraft, the Mirage IIIC remained the IDF/AF fighter long after the Phantom entered Israeli service.
While the Egyptian pilots do deserve criticism, I am not sure that we are not finding an easy group to blame instead of dealing with some really easy to fix issues at the top. Before the war, a civilian plane penetrated Egyptian air space by coming in via an indirect route over the sea. The Egyptians did not have radar coverage over that area. This prompted the Israelis to plan an attack via the same route. How hard would it have been to turn some of the radars out to sea? So we end up with the Egyptian Air Force being destroyed on the ground. Sounds like a failure of flag officers to me.
Even without air cover, the Egyptian army was generally holding its ground when the retreat order was issue. This turned into a rout, and yes this largely falls on field grade, company grade and NCO's shoulders. But retreating in good order without air cover is one of the more difficult actions in combat. Exactly how well the the well respected US Army do in the PI in WW2? Or in Korea? Even in the battle of the bulge, we had a division simply disintegrate. BEF fell apart in 1940 on retreat order. Retreats are really, really hard to do well.
So my argument is most of the blame here is not the lackies, but high level leadership. I can easily write an ATL where with the Egyptian army holds as the Egyptian Air Force is worn down at roughly the rate of the Israelis.
So while I think the Egyptian pilots are not as good as Israeli pilots, I am not persuaded the difference would have decided the war if we remove incompetence by the Egyptian high command. A bad series of decisions by a flag officer can cost a nation a war in a week or two. Not sure why we need such complicated answers to such an obvious failure.
We can say the same thing of the 73 war where a halt order by a Syrian officer saved Israel.
Or the 1948/49 war where the Israelis were out of reserves and down to their final line. Then a diplomatic pause allowed the Israeli to rearm but not the Arabs.
Really looks like to me the Israelis got three really big, lucky rolls of the dice. Let me do that to any other power not Nazi Germany, and I can wank the living daylights out of them.