That doesn't really make any sense. Prices will always correlate as long as there's any connection between asset prices whether it's a supply chain or shared cu

That doesn't really make any sense. Prices will always correlate as long as there's any connection between asset prices whether it's a supply chain or shared customer base or shared economic conditions. Businesses don't live in an isolated bubble. Index funds are nothing but arbitrary groupings of assets enabling diversification along whatever lines the fund chooses. I'm not sure what point you're trying to make but the argument is poor.