Figured that title would get people's attention (and get their ire up).
As a whole, I think this is true. I'm sure there are now about 2,000 people out there who are going to write me and disagree. I'll spare you the trouble: I'm sure your 1950's bass clarinet sounds great. I'm sure you can manage its intonation issues. I'm sure it's incredibly free-blowing. I'm sure the wood is incredible.
But, for my money, I prefer having the technological and acoustical advances that have been made over the past 60 years part of my bass clarinet's DNA. I like that the ergonomics of the instrument have improved. I like having a single register key. I like being able to not twist myself into knots to get the thing to play in tune.
Sometimes older is not better.
Let the flame war commence.