It turns out that much of the music featured in the original airing of the show wasn’t licensed in a way it could be used long term, and over the years it has been replaced with terrible stock songs or jarringly anachronistic choices that sound totally out of place.
Entire scenes and episodes have been cut from the seasons distributed on streaming platforms, because they featured live concerts that couldn’t be edited. The original had performances by the Flaming Lips, among many others, that simply can’t be watched now, except if by chance someone copied an old VHS to YouTube.
Music was a big part of the original show–in addition to the live shows it featured all sorts of great pop songs from the time, which was part of why it was such a hit with teenagers when it aired. It’s such a bummer they stripped it all out!
There are some places online with copies of early DVD releases that have more music, but still not all of it. The original is locked away in a vault somewhere and almost certainly won’t ever be enjoyed in a complete state.