I'd say the problem is that people are highly educated in general, and very poorly educated on many subjects.
A perfect example is Belton Cooper and his book "Death Traps"
I do recommend the book, it's an eye opener on many levels. Some of the stuff he talks about, like the development of the Super-Pershing is highly interesting.
The guy was "over there", he had ample hands-on knowledge.
But if you believe everything in his book, you're being sorely mislead. He shows that even the "experts" don't always know what they are talking about. Many of his claims are one part truth and one part misunderstanding. He fails to recognize a real "Christy" suspension, he doesn't know the difference between various models of Sherman or misidentifies them.
You can blame these on a lack of research and working from memory.
He also makes quite a few assumptions, stuff he may have overheard somebody claim and accepted it as the truth, such as the fact that Patton single-handedly held back the introduction of the Pershing tank or that the name Sherman was invented by a "Yankee" to spite all the southerners in the army …
The archives do tell another story.
Yes, Belton Cooper is a veteran, he was there, he saw many things first-hand, but he was not private to all the discussions that went on between AGF, Ordnance and all the major players involved. Cooper probably heard somebody repeat, like a bit of telephone game, the idea that Patton wasn't too keen on introducing a new tank because it would require retraining the crews and would add a whole new tier of logistics to support it. As far as he was concerned he was still advancing without these fancy new tanks. Note this isn't Patton telling Washington to stop all work on the Pershing. He was only one of the many people consulted on the subject and to the shock of most wargamers, many commanders, including the "fighting officers" who drove tanks as a full-time job were not keen on getting new tanks either.
And this is where people, no matter how well educated on a subject will go wrong.
"How can they not want the Pershing ? They must have been incompetent idiots !!!"
There is a very interesting rule of thumb I came across a few years ago :
If you see a professional make a decision that to you sounds wrong there are two possibilities, either they have made a mistake, or they know something you might not.
To wrap up the point, there is a lot more to the Pershing debate than simply comparing armour thickness and gun penetration and conclude that anyone with an ounce of sense would have dropped the Sherman as soon as the Pershing was even mentioned.
If you follow the Cooper narrative you will conclude that the Sherman was the worst possible tank and that highly incompetent idiots did everything to stop any improvement leading to the death of tens of thousands of people. This conclusion is based on the opinion of an expert who was there and witnessed it all first-hand.
If you follow a broader narrative, you will understand that the Sherman was subject to planning based on certain assumptions and out of date information, that the US army had to deal with moving equipment across two oceans and any bad mistake could cause thousands of "perfect" tanks to sit idle in a parking lot leaving troops without tanks instead of giving troops an "adequate" tank that was available in huge numbers.
Sherman was quite adequate for most tasks, but it happened to be inferior to German tanks because of their fixation on armour and firepower above anything else. Shermans were designed to run in places the Panther would have fallen to pieces. It was designed to do more than just knock out enemy tanks and it was designed to be repaired in the field, as the US army didn't have the capacity to ship back tanks to the factory for a full repair like the Germans did. Just the amount of work that went into figuring how the effects of heat, humidity and general tropical on the rubber parts of the Sherman is pretty impressive. They may not have had a boner for big guns and thick armour, but they did take many factors into consideration that were not even an afterthought to the Germans.
Same story for the British, why were they unable to build a better tank ? Simple answer : they spent all their effort on building ships and planes, only a tiny % of the budget went to tanks. Tanks were not a major priority when it came to the British war machine, planes and ships were.
To return to the OP, many of us, on any given subject may only know the "Belton Cooper narrative" and parrot it endlessly because we are unaware that we only get a distorted one-sided story. And for lack of understanding we think we are the enlightened with a laser-like focused vision who understand any problem to a far greater degree than any "so-called "expert""
But then again there are many people who think Dunning and Kruger are complete idiots because "What do they know ?"
"Throw the first stone he who is without sin." I bet a lot of people would be highly offended if Jesus made an objection when they smiled, declared themselves without sin and stooped to grab a stone …
shows how to make roads, using the formula of the late Ian Weekley.
-heads? Just want once I would like to go a day where I can read The Miniatures Page and not seeing someone posting some sort of asinine comment that displays either their ignorance of a subject, or their prejudice of people different than themselves, or their complete lack of courtesy, or their lack of common sense, or their lack of all of the above. 
