Catch Me if You Can is still a great movie, even if Abagnale lied about the whole thing. I mean, "inspired by a true story" or "based on a true story" movies already deviate pretty severely from history in many cases.

Here's a question though: did the writers feel they had to stick somewhat close to the "truth?" Did it cause them to make some choices they might not have if they were writing about a totally fictitious conman? And, if indeed those things happened, would the movie have been even better if they had total freedom? Or did the movie thrive in part due to its constraints? All unanswerables of course but an interesting train of thought. Reminds me of how the first three Star Wars films are the best despite their limited budget and Lucas' relatively constrained freedom of direction.