Unless it is a hardware or a software project of the scale of Chromium or GitHub with millions of users, there is nothing that can stop Microsoft from rolling their own version. This unfortunately just confirms that once again.
Typical EEE here.
• Embrace: Microsoft privately contacted the single primary developer of AppGet (a package manager; libre, copyleft, Apache-2.0) about potential employment.
• Extend: Microsoft implemented WinGet (a package manager; libre, permissive, MIT) privately on their own, borrowing from AppGet's architecture (design-wise, not code- or library-wise).
• Extinguish: Microsoft publicly unveiled WinGet after providing advanced notice to two external parties, the development teams of the existing Windows package managers Chocolatey (which commercially sells functionality WinGet doesn't subsume) and AppGet (i.e. one person).
None of these are EEE, except arguably Extinguish with AppGet. But you're moving in that case from an Apache-2.0 licensed solution to a MIT licensed solution, when modern Microsoft has proven to have decent respect for their permissively licensed source releases. This is a phyrric victory for AppGet.
They didn't get back to him, but MS recruitment folks (who work at some sourcing firm and generally don't care about their role) have been known to do that.
Why didn't he chase them though?