Something I've observed over the last several years of red-pilling is that some people are physically incapable of understanding the truth. If you confront them with information that they are not prepared to accept, their brain perceives it as a literal threat to their safety. The Fight or Flight response takes over their brain and shuts down their ability to process the information. They start shouting/insulting (fight) or try to shut down the conversation (flight) as fast as possible, even when they normally don't act like this.
I once had a half-hour red pill conversation with a family member. A few weeks later, I reminded the same family member of this conversation. They had no memory of it. None at all. They haven't displayed any memory problems before or since. It's just that one specific conversation they don't remember. I'm convinced their brain physically blocked it out of their memory.
We all have our own theories about Q's "the truth would send 99 percent to the hospital" comment. Well, the above is my theory about it–that 99 percent of people are physically incapable of processing this much truth.