The idea that there's a noticeable benefit to having a sample rate higher than twice the highest frequency is the snake oil here. Many audiophiles seem to believe this but it's not supported by the mainstream understanding of digital signal processing.
By lossless they mean “losslessly compressed from source” (FLAC, or likely in Apple’s case ALAC) as opposed to “lossy compressed” like MP3 or AAC streaming services usually use.
Wether or not the original recording was done/mastered in 24/192 or higher/lower is a whole other question. In the grand scheme of things all ADC involves “compression” in the form of quantization.
It means that the audio is sampled at 192khz and each sample is 24bit, not that the audio is recorded with hardware capable of recording sounds up to 192KHz
I know about nyquest, do you? 192kHz sampling rate means the highest tone representable is 96kHz, which is roughly 80kHz more then what the average human can actually (still) perceive.
For audio-postprocessing, I might be convinced that there is a benefit of raising the sampling frequency that high, but for pure hi-fi consumers? No way. This is snakeoil.
That's an unconvincing argument because the presence of ultrasonic sounds can affect human perception. It is just not perceptible via the exact same mechanism that ordinary sound is.
The argument you should be going with is that the speakers and headphones that people will be playing the music on doesn't do ultrasonic sound.
