I don't see any of those being conspiracies. They were beliefs which changed when science was able to prove them wrong.
At the time though people arguing against some of those things would have been labelled as crazy. The conspiracy theory statement has only really been around for around the last 50-60 years.
The key thing to most "crackpot" ideas that have been proven to be true, is that people accepted science to prove them. There have also been significant other crackpot ideas that have proven to be false, again by science and in the past people have believed that.
Probably since the Kennedy assassination we have seen people continue to "question the science" as they call it. Most conspiracy theorists use this term as it sounds like they are critically thinking, but to question the science, you need to provide actual evidence to counter the current accepted belief. That all started with the Kennedy assassination, that people still question the Grassy Knoll theory proves how these conspiracy theorists now exist. The bullet to kill Kennedy came from in front of him, we know the bullet hit Kennedy's head and then hit his security who was sitting behind him. The science proves this, yet people still question it, and the reason (and we hear this all the time), but thats because "they" want you to believe that.
At the crux of almost every conspiracy theory is the theory that someone is trying to control the narrative, that someone is trying to control the population and the fact that none of this can be proved, appears to be proof of the existence of this other body. Take yourselves back to the New World Order, this theory has been going around for decades, apparently some power hungry groups, will change the world order and control the population, yet it hasn't happened. Either they are incredibly patient and want their ancestors to get the benefit, incredibly incompetent or the narrative is false. This one reared its ugly head again through Covid. THEY were trying to control us, THEY were going to change our lives forever, THEY were going to restrict our ability to do things, yet here we are, 3 years after the outbreak and our lives are basically the same as they were before Covid was first mentioned.
Science to disprove science is great, and there are ideas that would have seemed crazy at the time that have been disproved, but as with all of these theories, its science that came to that conclusion and is a good way to decipher the difference between a crazy crackpot idea and a conspiracy theorist. Crazy crackpot idea welcomes science to prove the idea, conspiracy theorists claim the science doesn't prove their idea because THEY are lying to you, or restricting information or something along those lines.
