Humans do a great many things by default that are directly in opposition to determining truth. Look at any list of common logical fallacies. Every single last one of them is something humans do by default. They're intuitive and emotionally persuasive.

There is little similar between what was suggested by the person you're replying to and any policy which simply throws both opinions out. What he was describing was engaging with the content of an argument, not its speaker. This is proper. This is how things should be decided. "Who gets on TV" is an antiquated limitation which generated the difficult situation where someone has to make that call, and the unrelated constraint of needing to break for commercial or move on to the next topic in order to keep the audience engaged or keep to a programming schedule exacerbates it. The way the medium is used makes it impossible for a positions justification to be explained, only the position with no justification can be presented. This simply should not be done, but is the sort of thing which due to technological limitation was done out of desperation for a time. Commercial interests, of course, still motivate this approach, but those commercial interests, I think we can both agree, are not intimately tied to the ability of the medium to assist the audience in coming to a nuanced understanding of available views.

There is a very big difference between the ideal situation, where in every instance you have infinite time and access to all possible relevant information, and the practical situation with limited time (not 'oh I can't pay attention to one argument for 45 minutes' but 'if we do not do something before Tuesday, hundreds could die') and resources. It is not incorrect to discuss the ideal situation, because it will always be present and always provide the limiting constraints on the practical case. While you can be in a position where you could argue 'we should trust the expert because we have exactly and only 2 choices and his authority is better even though he can not explain it', even in that situation it must be admitted that what you are doing is wrong. It is a wrong thing which is being forced by circumstance to be done. In the ideal case, you are guaranteed truth. In the practical case, you try to do the best you can. In the practical case, the redneck might have a point (farmers, for instance, had been talking about global dimming for years before scientists gathered the data and became concerned... we were able to reverse it, but not before the pollution from England caused the jetstream to shift and led to several years of intense drought and famine (remember Live Aid? That was global dimmings work) in Ethiopia. Then you have cases where a doctor says other doctors should wash their hands between doing autopsies and delivering babies. He was not right because he had authority. In fact, the argument against him was that he was not respected enough in his field and that it was insulting to suggest that the doctors killing women and children left and right were actually at fault. Those were the more respected members of the medical community. We were saddled with leaded gasoline for decades because the community of research chemists all agreed it was safe and did so for financial benefit and based on very 'common sense' arguments (lead is so heavy! It will fall to the ground and not travel far from the road, how would it get in the air?). When a toxicologist reported the danger, he was met with insult and told he was entreating on chemists territory. Because people trusted the authority of the professional research chemists, he got ignored. Because of them having their authority trusted, they could not afford to even investigate the truth. If they lost that authority, and the trust, they would be done. All unnecessary and a tragic bit of scientific history every researcher should know. Those authorities are just people. They can be just as selfish, mistake-prone, prideful, etc as anyone else. It is not reason to dismiss them. It is reason to expect them to present you with solid evidence, solid argument, and to NEVER ask you to 'just trust them'. The same applies for the redneck. If he provides solid evidence, solid argument, and never asks you to 'just trust him', you review his argument and evidence exactly the same.