There are a number of WW2 myths that seem so pervasive. You'll see them in a huge number of documentaries, run into people discussing them, either out in real life or on the internet, and sometimes even see historians engage in them.
Some of the myths I'm thinking of are ones such as:
I've seen plenty of documentaries discussing the superiority of German armour, throwing out claims that for ever Panzer the Western Allies killed the Germans managed to kill 3, 4, 5, whatever, tanks in return. However, reading books on the battles of Western Europe a lot of the tank battles seem to have the Germans barely exceeding parity in the number of tank kills.
This perhaps ties in with the Sherman tank. Many documentaries, and books, will disparage the Sherman. It was a death trap. It burst into flames at the drop of a hat. It had paper thin armour. Its gun couldn't kill anything. Etc, etc, etc. If only it'd used diesel like German Panzers (Panzers actually used gasoline). Many documentaries will interview old Sherman crews talking about what a death trap their Sherman was. However, quite a few historians will discuss that it really wasn't that bad of a tank.
From the Pacific War you have the Sleeping Giant quote. It seems to be mentioned in quite a lot of documentaries, books, etc. However, it seems that the first time anyone ever heard this quote was in the movie Tora! Tora! Tora!
So, how have these myths, and others like them, managed to become so widespread, not only among the general public, but to the extent that they are quite common in things such as documentaries which you would hope would be better sources of information?
There is a confluence of reasons.
For example, TV documentaries generally are not made with a budget sufficient to send researchers to the Archives for weeks, as folks such as Zaloga and myself have. They'll grab the low hanging fruit.
Secondly, there was an actual tank scandal in 1944. It hit the US newspapers, and provided legitimacy to the idea that the US tanks were poor.
This scandal was generally perpetuated by the end users of the tanks. And, unfortunately, just because one is an end user, that not only doesn't make one an expert in tank history (only the tactical and technical effect of the tank you crewed), it also provides a very subjective assessment, usually focusing on a few criteria which were very important to the crews for a short period of time, but which did not necessarily reflect upon the overall capabilities of the tanks. In effect, on had an effect of the fallacy of an appeal to authority without any ill intent whatsoever. The veteran was there, that's good enough for most people, and nobody was inclined to dig deeper. Sure, some folks kept fighting the good fight, but they were often disregarded as being echelons above reality, despite having a very good overall view.
So, these veteran opinions entered into popular consciousness, got reinforced by popular media such as Patton (the movie) or books such as Death Traps, and that was all she wrote.
I should be clear, I am in no way disparaging the accounts of the tank crews. I am, however, strongly advocating against taking them for more than what they usually were: Subjective assssments of a very small data point.They have their worth, just not where most people focus. For example, Death Traps is frequently cited as to the problems of Sherman, how terrible a tank it was, why we didn't have Pershing etc. All total rubbish. However, I still recommend the book for the insight of what a junior ordnance officer experienced. If you want to see the history of the T26E4 tank up-armoring project, Cooper was there, and it is valuable for that.