MetropleX
Does not apply here - no Lawnchair nor any other defaults-surrogate apps installed.
I use the same set of apps on non-GOS AOSP derivates, where I don't have crashes on user profile switching.
What I THINK made a difference is the source of the apps - I moved profiles from one GOS device to another (same model, Pixel 7), by restoring with SeedVault (1-2years ago).
On the new device (same GOS version, same model), profile switching caused frequent crashes while it rarely crashed on the source device back then...
I also rememer having seen lots of keyguard and profile termination commits fixing related crashes, back when network location service was implemented in GOS.
Maybe some of them got lost at one of the QRP rebase pulls?
But that's just from memory, which isn't alsways source of truth... If I find time I'll search for the commits I have in mind, but I guess this won't happen since I don't follow GOS repo closely and it's simply too many - for a reagular user.
Meanwhile the lost landscape capability of the launcher/home screen (with the A16-QRP1 rebase) is driving me nuts - bicycle and car mounts are fixed landscape orientation - not funny to search the maps app while driving...