There are similar views from Linn and Naim. They are perfectly rational being based only on the fact of a balanced connection’s superior ability to reject parasitic noise ( CMRR). The argument goes that this is not relevant in a typical domestic situation where such noise is not prevalent. However it may be worth considering that this view was often formed some time in the past , in both Linn and Naim’s case prior to wi-fi and mobile phones which feasibly may have increased such noise levels. Of course an RCA/XLR connection will lose any such improved noise rejection therefore ,on this ground only, being the equivalent of a single ended connection.
However this view does not take into consideration that in dCS units the comparison is not of like with like but of two inherently different designs which both sound and measure differently. I will stay neutral on any subjective preference as the RCA design is also excellent of its type. However:
My own view is that, everything else being equal, I would only choose a preamp or amp with properly balanced inputs to mate with a dCS unit. However it may be felt that in any particular case other factors are judged decisive.