Anybody who upgraded to the new HomeKit architecture in December had the “configuring” issue fixed?
So far, I have not.
I updated each one separately by plugging in to my Mac and factory resetting.
Removed them from home and set them up new.
Setup went better and was promising, but now they are still stuck configuring and not showing up as stereo pair yet even though I did that during setup process.
Anybody else?
Here's what I do:
always do the updates manually
always update them from a device running the latest iOS/iPadOS/macOS (updated before updating the HomePods, if necessary; I would give best odds on updating from iOS or at any rate not macOS, since that's usually what's needed for original setup)
unpair any stereo pair(s) before updating
update one at a time, and test it after updating by playing something
re-pair the stereo pair(s) and test them again
No problems that way. There IS one oddity: since the update that enabled the HomePod Mini temperature and humidity sensors, Monterey (or any macOS prior to Ventura) only shows the Minis as "configuring", but that isn't breaking anything other than control or updating of them from those older macOS versions. I only have originals (3) and Minis (2), but I assume the new full size HomePods would be similar (or worse) with older macOS (or probably iOS/iPadOS) versions.
I did enable the Matter support and use a Beta of the Eve app to update my Eve smartplug to Matter, following all instructions. That worked and still works after 16.4.
Aside from being slow and relatively labor intensive compared to an automatic update, one minor annoyance is that any update (probably an automatic one too) causes them to forget the last song they played. That becomes obvious with the test playing in the procedure I described.
Occasionally I've had it require me to re-enter my AppleID password for updates. That's happened a couple of times lately, but not this time. I don't think it was REALLY necessary, more like a timing issue with the HomePod vs the device controlling the updates.
My WiFi setup is boring, a DLINK router/base station that I own, no mesh or relays (but separately named 2.4GHz and 5GHz SSIDs, so I know at a glance which one something is on). In a few cases, if I do something with the phone and a HomePod not long after coming home, the iPhone may be on the 2.4GHz because that has longer range and reconnected from the driveway, while the HomePod may be on the 5GHz (preferable for speed). For a few functions it complains that they're not on the same one, and the HomePod may "follow" the iPhone onto 2.4GHz. So if I'm careful, I make sure the iPhone is on 5GHz before using it to fiddle with HomePod settings.
My main laptop is still on Monterey because of the PITA of updating MacPorts (packaged open source software, has to be reinstalled after each major OS update) and breakage...but I do have a Ventura (or whatever is latest) VM for checking what works vs what breaks. And I have something still on Mojave because vpnd is said not to work right after that. (and a Snow Leopard VM with original Rosetta for a few PowerPC executables that are useful but were never updated) So I see things that break because of version mismatch issues (and device support not being backported)
I once had one of the original HomePods brick itself, but that was NOT associated with updating; it may have been a power bump, or just one of those random cosmic ray things (IoT devices and devices without a recovery mode REALLY need ECC CPUs, RAM, and flash, which might greatly reduce random problems; if my recollection is right, blame Intel for going cheap on consumer computers, even though bulk adoption would have minimized the cost difference; otherwise ECC might have been more widely adopted). Fortunately it still had a few months left on the AppleCare+; I procrastinated but did take it in still under coverage, so they just verified that the recommended procedures didn't help, and accepted it for swap; a few days later they had a new one to replace it for me to pick up. (I gather the inventory of spares is sparse enough that it had to be shipped from elsewhere.)
That's pretty much my entire experience with HomePod updates. Being a retired IT guy, I tend to do things manually because I want control and a plan for how to have the best outcome, or at any rate discover failures before they're any more widespread than necessary; and doing things too automatically is riskier, except in certain cases where one has done one's own extensive pre-testing on duplicate hardware. There are advantages to professional paranoia.

And to noticing details, which allows documenting a known safest (nothing is perfect) procedure.