Lots of good points made here. I agree with Nostatic in his assertion that Fender guitars/basses of the 70s are not as good as the ones made today. The CBS years were the worst in Fender's history as far as quality instruments.
But SloDave makes lots of good points and his observations are very valid. Check out this video and while you're there listen to demos of various guitars played by Phil X. He only uses a couple of different amps so you only hear the difference in guitars of various makes and vintages. You should be able to appreciate the difference in guitars made in the 90s and those built in the 50s-60s. If not, then it doesn't matter to you and that's cool too.