This hasn't been my experience. A lot of people say they think the moon landing was fake because they have a general distrust of anything the government says, and are particularly skeptical of anything from the cold war era. But they may still be willing to listen to reason if you approach the subject with a compassionate mindset, not shaming them for questioning authority but instead acknowledging the basic legitimacy of their anti-authoritarian skepticism. After all, the government has done shady shit before, it just happens that the Moon landing isn't one of them.

The depth of publicly available information about the Moon landings helps a lot too. Most people have only seen a few minutes of video footage at most, and may conclude that Hollywood could fake that video. But the amount of documentation about even the most minute detail of the Apollo program is staggering. If it were all fake,it would be the greatest most detailed work of science fiction ever created. Seriously, it would put Star Trek/Wars to shame. No fiction has lore with such fractal depth of detail as NASA, not even close. Not even Silmarillion comes close.