After that author’s post (from 2020) Microsoft acknowledged and apologized the bad way they went about it. (IIRC anyway.)
It’s certainly a shitty situation for the author, with the PM opportunity at Microsoft not working out (reason unknown/not visible to us). The author can’t invest as MS can into their project. The author could continue, but obviously, it’s less “useful” now as a product, with a “better” alternative.
Having it be a Microsoft-maintained project gave and gives it a lot more impact and significance, both functionality-wise and public-/enterprise-wise. Having an official package manager like this is a very good thing.
And the author on the post you linked says as much in their post. They’re not upset about anything else other than the communication in regards to the hiring process he was not that interested in anyway. That’s not really “stealing”. Just superseding. With an aside shitty-communication.