Yes, if you are referring to upmixing. OTOH, the use of discrete multichannel recordings makes that unnecessary.
Totally true, unfortunately the catalog of offerings is pretty slim, specially if your interest is rock/pop.
To compound the issue, many releases are packaged in these "reissues" that include vinyl, cds, books and posters, etc; and are priced at hundreds of dollars. I don't need all that extra crap, I just want the Blu Ray.
LOL
The whole thing does seem nonstandardized and therefore probably a little of a wild west thing from the studio sound recording to mastering to home playback. I have been given to believe that things are much more calibrated and standardized in the movie industry.
If you speak of upmixing stereo sources to 5.1, absolutely, it's all wild west and simply a users preference.
True multich recordings use mostly the same standards as the movie industry.
With 2 channel sources either stick to stereo playback or pick what upmixing software sounds best to you. There are a lot of options in software to chose from and some work better than others with each individual recording. Personally I've settled on Auro 3D for most recordings.
If your running an older component, I preferred Dolby PL II over DTS NEO6 for most music. YMMV