What you described is a lot better (read some pre-existing literature, to learn the opposing side's arguments and especially when corresponding with an academic, to read their prior writing). But usually even bad books are going to blow a DuckDuckGo search out of the water on quality. Especially for those who aren't astute enough to identify good and bad information.
I'm not sure how true that is anymore. If by "book" you mean "monothematic long-form treatise by a small number of authors" then I have read essentially zero books in the past year, although I have done a great deal of reading otherwise. Research papers, magazines, blog posts, Wikipedia articles, cherry-picked single chapters of books can in aggregate absolutely stand in for a few books. And then there are sources of knowledge that go beyond reading, such as personal experience, original research, attending talks, etc.
I think your test would be more accurate if you asked more generally how they learned what they know about the matter.
Example for me other than Marx & Engels that I mentioned elsewhere in this thread, is my passing interest in European Celts. I enjoy reading about Iron Age Europe, so I've had a hard time resisting books on the subject. Caesar's Druids by Miranda Aldhouse-Green was a recent book that I read and something I couldn't pass up. While I accept your statements and agree, I still think the same will be for you if you're truly serious about a given subject.
Nearly all of the best programmers I have met have never read a book on the languages in which they are experts.
Books are not conducive to learning about a whole field, they are just a way for authors to lecture you on their world view.
When I want to find out how something works I usually read a meta analysis or a review in a highly rated journal in the field. That way you get to see everyone's opinions and arguments on the subject. They are usually written to be more or less accessible for people not in the field.
I think that you're using the theme of nazism as a way to make an opinion from a protected standpoint -- it's difficult to refute what you say without sounding sympathetic to nazis.
But i'll say it anyway : I think you, and anyone else in the same boat, hold less authority on a topic without being well-versed on said topic.
It's really that simple for me.
Don't stop speaking to or throw out the opinions of folks uneducated on a topic, just weigh them appropriately along with the expert opinions.
"Making up your mind" without educating yourself on the topic is dangerous, no matter which side you start leaning towards.
I'm not telling you to go pick up 'Mein Kampf' -- not by a long shot -- but to condemn all books on the topic is frighteningly naive as a societal habit. It propagates a certain kind of sneaky "head-in-the-sand" behavior that may lead to even more strife in our world, and prevents the great historic feedback-loop of the knowledge of our past preventing historical repetitions of our worst atrocities.
I think a better example would be Marx's Das Kapital. I probably wouldn't waste any time talking to someone about 20th century political & economic history/theory who dismisses it out of hand.
And I can tell you the vast majority of Americans will dismiss it. The standard response to "I've read it" is: "What, you're a commie?"
I'm not a Marxist, but I have read Marx and Engels. If I had to be pidgeonholed into any political ideology that would be the vein I'd choose. I probably most appreciate Peter Joseph from the Zeitgeist Movement, which is similar and derided as "Communism with robots". But at least I've read a few treatises on the subject. I also went to Moscow about a decade ago, simply because I didn't want to form a strong opinion about a world power that everyone thinks they know about- without actually at least stepping foot on their soil myself.
In sum, people need to put their mind where their mouth is.
I do think society would benefit greatly if we cut out the masses who have strong opinions on subjects they haven't even bothered to read.
Your Nazism opinion for example, doesn't sound like it's based on much other than trendiness. If it were 1935 and you were in the environment where it were popular- someone like yourself would probably would be Sieg Heiling with your jackboots on, in all seriousness.
