Ivor Tiefenbraun started this source first thing back when sources (turntables/arms/cartridges) differed wildly. The thinking persists even now, apparently, but is not so valid as it was in the bad old days.
If you have opaque speakers and amps, how are you going to judge the rest of the chain - or are you going to take a chance and buy something that "they" say is good and trust that when you finally get to the speakers and amp and can at last hear your front end you will like what you hear?
Taste does come in to this, so as I said yesterday how can you make meaningful judgements until you have a revealing back end (which, it bears repeating, includes the room)