Why does the 'App Not Compatible' pop-up appear on iMac?

Hi. On my late 2019 27" iMac (i9, 72Gig, OS 14.6.1) at seemingly random intervals spanning days to weeks, less than a month, the pop-up above shows up. I've tried to diagnose the cause, but am not knowledgeable enough in how to find that to do so. My best guess is that some program wants to auto-update and is inadvertently attempting to download an Apple Silicon version. I've turned off Microsoft Auto-Update and I've gone in and examined my startup items to cull things that I thought might cause this. But what is left seems kind of necessary. No change.

Note that the pop-up is an always on top window and not associated with any program in Finder.

[Re-Titled by Moderator]