The original post, on its face, appears to be a reasonable cause of doubt. However when you consider the time and energy that goes into the process of professionally converting A to D, it involves a lot of time and money.
A couple of years ago a very famous producer was in her New York studio with the family of deceased jazz artist. She commented how are after they had remastered at the 192/24 resolution, she said “he was in the room”.
So I think IF a company or individual or insert the blank, takes the time and energy to remaster A masterpiece, wouldn’t they have the wherewithal to know that there are varying qualities of source material? It may be an assumption, but anyone that is serious about their trade and reputation in that field, you would think that they would want to source the best.
If we humble (sic) audiophiles recognize that there is better media, why wouldn’t these professionals?
BTW my Roon somehow switch the stream to Airplay, dumbing down the rez to 44/16. My wife commented “what happened to the quality of the music?“ It had been going into my preamp on HDMI. Gotta figure out how to get rid of an airplay…