I don't think that was really the author's approach--to let them learn from their own mistakes.

It was to quit wasting his time trying to correct their mistakes when they weren't ready to accept criticism.

Do you think you've changed many votes with your corrections? Even in arguments you won?

> Whether the earth is round

I honestly think a lot of the flat earther types in particular are basically trolls and/or enjoy being stubborn/argue about common knowledge, for no other reason because they can.

> what if

Thats the thing. We never really know if there will be consequences. If a flat earther became president what would be the consequences? Will we still have AC in the summer and heat in the winter, food on the table etc? Its fruitless going down the rabbit hole based off "what if". Look at the last US election. If Trump becomes president democracy is dead! I think our (assuming ur American) is the strongest its ever been and I didn't even vote for the guy.

> ... there is actually an ever-increasing number of things that used to have an absolute right (scientifically proven) answer that become controversial. Climate change. Vaccines. Whether the earth is round - that kind of stuff.

I think there are multiple things here that need to be disentangled. The first is that just because science "proves" something that doesn't mean the political, civil, or economic path is nearly as clear cut. While there certainly are people who just deny these things outright there's also the camp that accepts the scientific result but disputes how to deal with it as a society.

Second I've seen an alarming rise in what I would characterize as scientism, a belief structure around science itself where the "acolytes" of science do not understand the science themselves, but use it to reinforce their own worldview in the same way that deniers (heretics really) use other sources to reinforce their worldview. I have seen this play out within my own social circle as people will defer to experts as if they are a clerical class with divine authority to determine ultimate truth. To give an example in a much less controversial arena, how often have you witnessed people adopting fad diets because the "science" shows X is good even though the actual backing papers, that no adopter has read, are much more murky at best? This is an understandable consequence of having a limited lifespan where not everyone can know everything therefore heuristics must be used to comprehend the world, but the flexible heuristic which can lead to a change of opinion can be swapped out for a rigid belief that permits no change of opinion unfortunately.

Last I think this ultimately stems from what F.A. Hayek called constructivist rationalism[1], the idea that we can rationally construct our own social order. I share your own concern about mistakes that affect all of us specifically regarding philosophies that adopt constructivist rationalism such as the family of collectivist ideologies (socialism and the like) which are currently on the rise. My conclusion is that civilizations will evolve according to the culmination of all individual actors' actions and I personally have a limited role to play, although I am a classical liberal. Your last question unfortunately can lead some to conclude that a much more dictatorial society is necessary to produce a result that may itself not be possible and instead lead to an even worse result than the alternative.

[1] I highly recommend The Fatal Conceit by Hayek if you want to challenge assumptions your own worldview likely rests on without even knowing it.