For the copyright part, it wouldn't have lead to a different outcome. What could have been different is that Microsoft could have had difficulties in working on a GPL fork which is harder to resell (you can, but people are sometimes afraid for good or bad reasons) and so Microsoft could have proposed to the author to sell them a copy with a different license.

But reading the article, the author appears to be more disgruntled by the fact that a behemoth forked his project than the mishandling of the copyright that can be fixed with one PR (he is right to be pissed about that, but that's an easily solvable problem, I doubt Microsoft will stand against it).