Are Expensive Balanced Interconnects Necessary?

Differentially Balanced kit means 2 totally independent channels (not touching each other), including 2 separate power supplies (one for each channel/L/R), but often a single PS is substituted. How critical 2 v 1 is I don't know, BUT,....

Doesn't it make sense that totally isolating the channels (no cross talk, or other potential compromises) would provide 2 pristine  channels? And if you understand that, THEN... how can ANY SE kit be true hi-end?

You can get great XLRs for not much money IF you buy them from Ali-Express. I have the white ones which are amazing and very inexpensive