Lol absolutely not, if it gives you more enjoyment and more miles then go for it!
Unless you use one of those ahead stem adapters/swapped fork to a non quill one, those are bad, bad people and should not be trusted, if this is you I'm afraid there is no salvation 
I'm running 9/10 speed on all my vintage frame and love it. Even went as far and had a custom frame made that reminded me of the elegantly shaped vintage roadies
