This has been an ongoing issue for years. Apple Music shows the following for me...
iPhone (about 90% of the artists have the artist photo instead of the grey microphone)
2020 Imac (about 60% of the artists have the artist photo instead of the grey microphone)
2023 Mac Studio (about 03% of the artists have the artist photo instead of the grey microphone)
I rebuilt my Music Library by hand this weekend because I had to manually migrate my data to a new internal drive that was much smaller. (Migration Assistant just grabs your entire computer and moves it to the new one) I used this opportunity to also clean up my Music Library as I was having many issues with old songs/albums ripped from CDs on my phone. They would sometimes display incorrect artwork, not play, or show duplicates in an album. All super annoying! My new library is pristine and working perfectly on my new Mac Studio — all except the Artist Images. I plan to transfer it to my phone shortly but was hoping to get that resolved before doing so. I may just do it since Apple has ignored the issue for soooo long.
I have spoken to apple support at least 1 or 2 times a year for the past 4 or 5 years. They NEVER do anything about it! I know I have not been alone on this issue. It is sad that it has been neglected for so long but... Today I escalated the issue with Apple support. They asked me to give them a screen recording and send some com files along with my description of the issue... They said they will send it all to their engineering team and let me know next wed 7/10/2024. We will see what happens! Fingers crossed but trying to remain skeptical. LOL
I can also tell you it is true that it is up to the artist themselves or their record company to provide an image in the first place. I saw there is now an artist page devoted to them through apple allowing them to do it.
https://artists.apple.com/support/1114-add-your-artist-image That said, we are at their mercy so if they don't make an image available we will be stuck with the gray mic for those artists.
The solution would be so easy... Just add another button below the "Get Album Art" option that says "Get Artist Image".
Please apple fix this so insane, perfectionists like myself and some of you can finally enjoy our music in mental peace! LOL