We finally figured out what made the Stradivari violins the best in the world after all this time. They were made from 1660 to 1750 and we've been unable to match their quality ever since. Turns out, it was the varnish. https://arstechnica.com/science/2021/09/study-confirms-superior-sound-of-a-stradivari-is-due-to-the-varnish/
@estherschindler
I was about to respond with a link to the 2012 double-blind study where the Stradivari ranked very low in player preference, and I was pleasantly surprised to see that this article included it. Recommended reading.
One thing this article does not mention (but that 2012 study does) is that even the best examples of these instruments sound different today than they did during the age in which they were made. Micro fractures in finish, the wood itself, etc.