Is buying a 'vintage' frame worth it?

i'm saying that if someone has to ask this question it's because the person isn't fully aware of the variables involved and shouldn't be buying expensive bikes.

I don't identify with this thinking, at all. Cheap bikes can be a pain in the arse too, and every damn penny you throw at them is infuriating because let's face it, once you've solved any and all problems, you still have a cheap shit heavy bike.
Spending the money to dial in a quality frameset to fit your needs will repay you with every pedal stroke.