Now think back to what Dubya said after 9/11/2001, with regards to questioning the news. "Let us never tolerate outrageous conspiracy theories regarding the attacks of September 11..."
I would suggest that tolerating outrageous or ridiculous ideas is what filters them out. If they aren't tolerated they don't cease to exist. And if the so-called conspiracy theories are so outrageous, why the need to hide from them? It's revealing how shame and ridicule are used to undermine the credibility of those that arrive at their own conclusions. The subtle threat contained in the President's missive is that it's "us vs them", and by espousing contrary views, you are then put in the "them" category.
If ridiculousness was the standard of what is and is not tolerable, there would be very few opinions at all, considering how simple it is to construct a strawman mischaracterization of an opponents views, and proceed to ridicule and attack it. Also, note that "ridiculous" is entirely subjective, and those who laugh at absurd conspiracy theories are usually guilty of believing just as many ridiculous things. A large enough cult becomes a religion, and with size comes perceived credibility. Mass media is the dominant world religion and it is the standard of truth, like it or not. All mass media accepts the existence of the moon landing, the official story of 9/11/01, and most establishment history and science. This is true no matter which side of the political spectrum one is on.
Mass media is a monolith, globally. World government is united backstage and one of their main strategies to remain concealed is the targeted-gaslighting of critical thinkers.