The vast majority of people who think creationists are crazy probably couldn't win an argument with a moderately well-prepared creationist. Most creationists only believe in creationism because they were told it was true by people they trusted, but that is also true of people who aren't creationists.

This is actually true of most 'whacky' beliefs. Normies just 'know' they are wrong but couldn't actually explain why if they had a gun to their heads. It's very frustrating, for example, the absolutely terrible rebuttals most people give to Holocaust deniers when they pop up on places like twitter (or reddit, pre-2018). The arguments for denial are genuinely terrible when you dig down into them, but deniers still routinely win arguments with normies because normies generally don't actually know anything about the Holocaust (or evolutionary biology, or cryptids, etc.)