I'm increasingly feeling that NDA = Naivety, and is a useful signal of a startup founder who is in love with their idea but doesn't appreciate that execution is

I'm increasingly feeling that NDA = Naivety, and is a useful signal of a startup founder who is in love with their idea but doesn't appreciate that execution is everything, so will undervalue everyone else's contribution (including yours) because 'the only reason we're all here is because I had the great idea'. Definitely not universal, but common enough (in my personal experience) to act as a very useful guide. If I get resistance (about half the time the person is happy to talk with me anyway) a good follow up question is "Who are your 3 biggest competitors?" If they can't name them, then they haven't done any market research either and their idea was likely conjured in a basement with no validation. "NDA Request + No Market Research = Solution in search of a Problem", and I'm not going to lose any sleep over not taking those meetings / missing those clients.