Even in "loud" music 10 or 12 bit is definitely noticeable. Many modern samplers include a legacy mode meant to mimic the grungy sound of old 10 or 12 bit sampling hardware. It might not be noticeable to non-musicians, but anyone who makes music will hear the difference. Even if you turn off other features that are usually included in tandem, like dac emulators.
That's when it's used as a "bit crusher" effect by converting to 10/12 bit samples by simple truncation, rather than dithering (randomized rounding up or down to the nearest quantization value, with P(round_up) = the relative closeness of the sample to the upper quantization value).
With dithering, the only difference a smaller bit depth makes is a higher noise floor, with the noise being just background white noise (like tape hiss). With most pop music a 10 bit depth with dithering would likely not be audibly worse, since pop music is usually compressed into like the top 10dB of the dynamic range.
