Your premise that there are bad ideas that need to be studied and actively suppressed by authoritarian means is flawed.
And yes, I firmly believe there is such a thing as "bad ideas" in the sense that they are harmful. Can that be abused? Absolutely, but we can't over-correct and say that no idea should be labelled "bad". Take climate change. For years science told us it was coming. Misinformation about climate change has made it harder for us to do something about it, and now we're living the reality of extreme weather events. Why would we not want to know how that misinformation spreads, and how best to combat it?
> Why would we not want to know how that misinformation spreads, and how best to combat it?
You don't get to suppress ideas in a free society, no matter how much you may disagree with them. You can discuss them and even try to win people over to your viewpoint through debate, but at the end of the day you can't force people to believe something without violating the social contract.
We combatted the ridiculous notion when masses of people thought they could cure diseases by burying a rotten fig under a dogwood tree on the 13th tuesday of the year if it was raining, and we did this by teaching people why that is ridiculous.
Understanding how and which absurd ideas enter people’s heads is incredibly important. And for many reasons that have nothing to do with “authoritarianism.”