...totally a speculation. Let’s see the data.
Ironically, the most definitive paper on this was published by Bob Stuart in the Journal of AES (peer reviewed):
Coding for High-Resolution Audio Systems*
J. ROBERT STUART, AES Fellow
On the need to go beyond 16 bits:
"This analysis of the dynamic-range capability of the 16-
bit 44.1-kHz channel makes it very clear that it cannot be
considered transparent. Even in the absence of quantization
distortion introduced by defective processing, the
benign noise introduced by quantization and dither is
audible from modest acoustic gains (around 100 dB SPL)."
As you see, 20 bits/120 dB is a bit more than what we need and hence you always hearing from me that -115 dB is the threshold we should aspire as far as full transparency.
His arguments for sample rate is softer and requires buying into a bit more ultrasonics being audible (at very high amplitudes) and room for noise shaping: