A huge portion of all compressed media files are poorly compressed files. Often these poorly compressed files come directly from music distributor with the wrong compression settings, or with really really bad noise. Remember, many music distributors are working with old systems (unable to upgrade either due to driver/software or licensing issues), outdated software, and plain old junky audio interfaces, etc.

Lossless (when used properly and able to algorithmically guarantee what comes out == what goes into the compression toolchain) avoids the whole issue altogether, and that's what's valuable about it.

Focusing on whether compression captures every nuance of uncompressed sound is the wrong battle. The real battle is against careless distributors and bad artifacts introduced by poor compression settings and often incorrectly coded compression utilities used throughout the music industry.

(ie we on hn might all be using Lame or the Fraunhofer mp3 encoders, but a lot of music producers/distributors will be using custom / closed source encoders, or even audio workstations with the encoder implemented in hardware, and those might or might not be encoding mp3 correctly.)