I think the bigger issue here is when do measurements no longer matter? Can people really tell a 110 dB SINAD DAC from a 120 dB DAC? Outside of laboratory conditions, I seriously doubt it. So, when the measurable differences become tiny to irrelevant, I'd expect personal preference to become more dominant in component selection.
For instance, because I have a mostly Bryston system, I would prefer to have a Bryston BDA-3 to a Topping E30. But, I would greatly prefer to pay the E30 price. If the price differential were not an issue, I'd buy the BDA-3. I probably could not hear a difference in a blind, level-matched test, but I'd be happier with the Bryston on aesthetic grounds alone.
For instance, because I have a mostly Bryston system, I would prefer to have a Bryston BDA-3 to a Topping E30. But, I would greatly prefer to pay the E30 price. If the price differential were not an issue, I'd buy the BDA-3. I probably could not hear a difference in a blind, level-matched test, but I'd be happier with the Bryston on aesthetic grounds alone.