I mean, the title is “Getting Forked by Microsoft,” not “Microsoft Removed My Copyright Notice.” They don’t even outright state that the fork is missing the required attribution, you have to infer it.
Anyways, the real question should be: what is the most productive form for the project/technology? Separate efforts may not the answer, we're looking for.
Yes, he complains in the last few paragraphs that he feels like this form is a competitor. Says that users sometimes come to him asking for help with the Microsoft fork, etc. Those all very much fall into the domain of "what did you think MIT meant exactly", imo at least.