Older instruments sound better, ate this true and why

[Ronen Tat]

Hi Ken,
To your opinion, for the sound to be changed over time, is there a need for strings to be vibrating on a bass?
Taking into account the time your neck and body blanks sit aside, waiting for their time, I would expect that by the time a bass is built the woods has already stabilized.
How significant would be the change in sound (over time, on a bass) with such woods?
Do certain woods tend to change in sound more than others?...