The Microsoft 365 admins at my workplace were doing something like this. It’s got some sort of built-in phishing simulation functionality (I think it’s this: …microsoft.com/…/attack-simulation-training-simul…). The idea is that the recipient clicks a button in Outlook to report it as suspicious, and get a “congrats you did the right thing” notice.
However, it seems like IT security were unaware of the test, because they started blocking the emails and blackholed the domain the emails linked to (meaning it doesn’t resolve on our network any more). They also reported the domain as phishing to some safe browsing vendor we use, which propagated into the blocklist Chrome uses. It was a shared domain Microsoft use for this training (it was one of the domains on this list: …microsoft.com/…/attack-simulation-training-get-s…) so Microsoft probably had to deal with un-blocking it…