I deal with the record labels everyday. We always request linear files. Many times you can see the rolloff in the spectrum analyzer and know it’s been upconverted. What’s worse they don’t realize it. I have actually had files for early releases from the studio that way. Audio files in the editors are solid blocks with no dynamic range across all music formats. It’s like someone took heddeclippers and cut off the tops.
Many times it’s the same with the remastered releases. They’re remastered hot/loud. In some cases we revert back to the original CD releases.
I've notice the same with re-masters. However, often times the master tapes are also RE-MIXED that adds to that difference. Unless you want re-mix on songs you think certain arrangements/instrument volumn would work better (Out of Time - Stones), be careful when buying a re-master.