Hmmm interesting. As a former software engineer I also support legal software...
But the trial of WIn11 I installed on Hyper-V when I was setting up my Intune config has never shown any signs that it needs activation. Now I know the docs are a bit vague about when and how it actually kicks in but I never bothered to investigate because the whole point of the excercise was that I could provision a new machine in minutes so could have a rolling 90 day trial forever. but your post prompted me to go and check and I found this...
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The host machine is Windows 11 Pro so its not a piggy back. I don't believe business is an official release name (it behaves just like Pro), and we don't have any corporate licencing agreement. There is an O365 business licence associated with the MS account I use on that machine but (AFAIK) that does not entitle me to Windows licensing. I have done a fresh start on this VM several times (using Intune) to test stuff, and on the odd occasion when I completely screwed it up
I guess there may be an outside chance its picked up an old digital retail licence from 7,8 or 10 that I had forgotten about - but I always thought you had to de-activate the old machine online to throw the licence back in the pool

But like you, I am treating this as a legit system.