I did read the article, and also the design doc which I linked in my top-level comment. The facts are that they started with TypeScript and moved away (for a p

I did read the article, and also the design doc which I linked in my top-level comment. The facts are that they started with TypeScript and moved away (for a particular internal component). The interpretation of that as wanting to use it and failing is yours. You could just as well see it as having made a mistake and then realizing it. But all of these interpretations, by those of us who didn't have to make the choice and weren't there when it was made, aren't very helpful.