A little late to the show, and to refute your statement once and for all…
Reminded by a more recent post of yours, in REW I finally generated my own 48kHz/24bit/-120dB square wave test signal and was able to (just) pull it into audibility without any sign of accompanying noise with my much cheaper, lowly SMSL M300 MKII DAC via its balanced variable output at the max to my DIY Hypex NC400 FrankenAmp and DIY full-range line-source speakers with their more current measurements starting from here.
And with some classical music, I’m even riding my volume maxed out when listening, so I’ve got the perfect gain structure for my system to make use of all that resolution.
… just sayin’ …
Look at that tiny test signal analysis wiggle at the bottom with the cursor at 1kHz
HAPPY LISTENING TO ALL