Saving Music library astoundingly slow

This is not so much a request for help - as I don't think there is a solution to this problem - as a sharing of the challenges I have been facing with the Music app in the hopes of any insights from others with similar experiences.

I have a very large library of songs (approaching 30,000 - an absurd amount I grant you) on my Mac, almost all of which I accumulated with iTunes over the past two decades. These are sorted into many hundreds of playlists that draw on both iTunes Store purchases as well imported CD material. And the artwork is drawn from a multiplicity of sources as well.

For other reasons, I stayed a very long while in OS Mojave, and then in the past few months I upgraded to OS Monterey (stopping over in Big Sur for a short stay before moving on.)

In any event, I didn't know that OS Mojave was the last stop on the iTunes train, and Apple has since moved on to the Music app. What ought to have been a seamless transition of my library from iTunes to Music has been anything but that. However, with the help of a number of Support Community threads, I was eventually able to work out a way to move my playlists into my Music Library. However, about half of the artwork didn't make it over the hump so to speak, so I have been slowly replacing the missing artwork, album by album and in some cases, song by song.

This is a long, slow process, but doable. Except for the fact that, unlike iTunes which would quit in very short order usually, the Music application will take at least an hour to fully save a moderate number of changes to the Music library. For a more extensive set of changes (mods to, say 20 or more playlists) the saves can take much longer, and in the present moment the application has been "Saving Music Library..." for a full 8 hours since I requested a Quit!

I would much rather not Force Quit, because the changes I made took a couple of hours, and I would have to put them all back in again. So I am willing to let this play out, but if it's still chugging away after 24 hours, I may throw in the towel and be a little bit less ambitious with my updates.

Anyway, it's quite clear from the discussions I've read in this community that this is a well-known behavior of the Music app, and there does seem to be a correlation between the size of the number of songs in the Music Library as well as the number of changes made to it to the time it takes to save changes to the Music Library.

In the present ongoing Quit - which will be headed toward 9-hour mark when I post this - I have been watching the CPU usage by Music in Activity Monitor. It is using a whopping 0.1% of the CPU! If you like to watch paint dry then you can watch the elapsed CPU time slowly tick upward, adding a hundredth of second of CPU time every few seconds. I kid you not!

I tried shutting down all applications except Safari to nudge up the CPU usage, but that makes no difference in the CPU allocated to Music. Right now, the only user applications running are Activity Monitor, Music, Safari, Stickies and Finder. The System is running at 2.23% and User at 8.07%. So the machine is Idle close to 90%.

I suppose there's a good reason why Apple's developers have allowed Music to consume only the bare minimum of CPU time. But clearly those limits are wildly out of whack in the case where a user is trying to save a large library. By comparison, this discussions process is getting about 6% and Safari is humming along at 1.3%. And I just saw the Logi Options Daemon pop up to 0.9% momentarily while Music's 0.1% share hasn't budged for the last two hours that I've been watching.

So why is Music being so impoverished for CPU time when the CPU is basically idling? Be interested in hearing your thoughts on this.

Thanks.