Microsoft funded Simon Peyton-Jones (Haskell) and Don Syme (F#) and SP-J worked on Excel, but it would be inaccurate to say that their goal was to rewrite Excel, Windows, C#, .NET into functional programming. Yes, to an extent researchers "play around on a whim doing hobby projects for fun", or more formally as SP-J said in an interview "the mission statement that Microsoft Research had at that time which was to push forward the boundaries of knowledge; put Microsoft in a position to be agile when new stuff heaves over the horizon; provide a reservoir of expertise for the rest of the company to draw on".

- https://archivesit.org.uk/interviews/simon-peyton-jones/

Otherwise your position is that "blue-sky research" doesn't exist (it does) or that big companies don't fund it (they do). In particular, the LinkedIn in question said nothing about "Windows", that is something internet has hallucinated to maximise ragebait.