I can agree with this 100%.
Also as of now, I have encountered one issue related to this tag when using scripting. The issue is with Vorbis tags specifically. When using $setmulti(ALBUMARTISTS,%_albumartists%) , Picard does not match it to my uppercase ALBUMARTISTS tag properly, but loads it as albumartists (lowercase) instead and would write a second set of this tag after pressing save. ID3 is properly matched to TXXX:ALBUMARTISTS.
Here is a screenshot from the Vorbis (FLAC) file to showcase this issue:
Before that, I was using $setmulti(albumartists,%_albumartists%) , for which the Vorbis tag was matched correctly and only one set of this tag (ALBUMARTISTS) would be written, however in this case Picard did not match it to my TXXX:ALBUMARTISTS ID3 tag properly and would write another TXXX:albumartists tag instead (obviously).
Since ARTISTS tag does not have this issue I assume that this is only related to mapping tags via scripting, but I just wanted to mention this in case it would be somehow relevant to ALBUMARTISTS tag specifically.
@outsidecontext Keep up the good work and I can’t wait having this tag as a default tag (hopefully) at some point in the future! 