I would wager there are many, many subjects that fall beyond the understanding of most people. Advanced theoretical physics is probably on the list. An in-depth understanding of chemistry, biology, economics, geology… the list is endless. I’d hazard a guess that history is another highly misunderstood field.
I’ll confess that a lot of stuff like physics, economics etc, is beyond my grasp. I don’t pretend to understand it either, except for some rudimentary aspects. Some people… well, some people think because they’ve watched a YouTube video that they suddenly rival biochemists, computer engineers, and various other experts. A lack of genuine understanding of facts (particularly around the sciences), combined with hysteria and fear-mongering (see the outrageous fear-mongering over the covid-19 vaccines for an example) can lead to all sorts of dangerous disinformation.
Perhaps that is what most people don’t understand, namely that the assumption of knowledge is a powerful and dangerous thing. People aren’t wise to how disinformation can poison minds.