If Microsoft can't hire people to be able to design a webpage that renders in all web browsers, then they have fallen much further than I would have even made fun of them.

If there's documentation that renders correctly in modern edge but is unusable in Chrome(ium) or Firefox then that would be useful to see.

It's a valid concern but I'm fairly certain it's nowhere near the top reasons that they do this. They have a history of trying to shove users into Microsoft's unwanted browser against their (often informed) wishes.