No, the test doesn't show that Stradivarius violins are junk but rather that the best violins by modern violin makers are able to challenge and surpass Stradivarius violins.
It's not a good comparison because there's much more range in instrument quality than cable quality.
"Audiophile speaker cables" carry the stigma that they do because the luxury versions aren't better than the "minimum viable product" versions in appreciable ways. Instruments, violins included, see a massive range in quality between the things you would consider functional violins and very well-made violins.
The complaint about audiophile speaker cables is that they don't produce a difference in result that even trained sound engineers would be able to reliably identify. Whereas any reasonably experienced violinist or even any reasonably experienced musician would be able to tell you about the difference between a bad and a good violin by listening to them. The differences between the best violins might be hard to identify, but there's still a substantial range of quality levels.
No, I would instead state is as modern expensive violins are of the same quality if not better. However you first have to remove the cues players have in identifying the violin they are using to remove inherent bias
