First of all, I try to remain open to learn from all possible sources.
Sometimes, even the dumbest statement or most uncritical thinking will lead to a revelation.
Ego gets in the way for a lot of people. They cling to ideas that become them. If you attack the idea, you attack the person. That should never be the case. So, putting your data out there can be a waste of time, unless it's a public forum where other people will see the response.
Even on something as important as 9/11, where current and future decisions are being made based upon that lie, and people continue to die because of it, it's usually best to leave the person who doesn't get it. Leave them behind and contact as many people who are open to looking and discovering. I believed the Bush conspiracy theories for 10 years, simply because I didn't take the time to look for alternative viewpoints. Then I read some science articles that blew my mind and showed without a doubt that 9/11 was an inside job. Even the debunker videos I've seen debunk nothing, but at best only offer reasonable alternatives.
Overcoming normalcy bias is tough. People have their comfort zone and feel threatened when you point out the crimes of the government they've trusted all their lives. One approach I've heard about is simply to ask good questions and to get the person to look. But even that doesn't work when they have preconceived notions about what is possible. Like one individual didn't believe secrets could be kept. As if the CIA and NSA are made of Swiss cheese, leaving holes for all to see what they're doing. I think not. And some secrets may remain that way forever, so we will never have any "proof" of them.