Here's some discussion about it: https://serverfault.com/questions/967452/windows-server-2019...

It only happens on Server 2012 R2 when "Desktop Experience" is enabled and you're logged-on with an account that would have groups stripped from its token by User Account Control.

I've no doubt it's related to UAC, ultimately, but I've nearly reached the breaking point w/ my disgust with being unpaid outsourced QA for Microsoft. Deploying and supporting their products have been my livelihood for 20 years, but the "new Microsoft" in the Windows as a Service era is straining my ability to recommend them.

That explains why I've never encountered it, and why it may have gotten past MS' own testing --- I know MS employees who use the server edition of Windows on their development systems, but almost everyone turns off UAC because it's such a pain to work with.

Also on server editions of windows, the system (by default) will ask for an "unplanned shutdown" reason, which is another modal you have to go through before it actually shuts down.