To be fair, people who think Earth is spherical or oval are also wrong, it is perceived that way because of space-time-gravity.In general, when communicating with certain people who are absolutely convinced that they are right and 'have done their research', whether or not they actually understand that research does not seem to be taken into account by them, the tone comes across as 'I know what I am talking about, more than you do, because I have spent countless hours looking into this', It does not matter whether they are talking to a doctor, a professor, a nuclear physicist, or a neuro surgeon, they have formed their opinion and that is that. If you disagree, you are wrong.
A lot of times you will find that there is lack of understanding of the sciences, where a hypothesis is made and then it is torn apart from a million different angles to determine whether on not it is correct. We all know that that is how science works and is continually improved upon. But to have an attitude where 'I am right, you are wrong, don't try to challenge me!' .....although generally founded from ignorance, as you correctly state, tends to give that person a 'feeling of authority' based upon what they think they know.
A great example of this, is a flat-earther who thinks that he is super intelligent and can completely ignore science-based evidence: