When had Microsoft done this before? For Cortana maybe? I can't recall them ever mandating dedicated physical keys for anything other than the Windows key, but that was over 30 years ago and I assume that's not what you're talking about.

Ah, my memory was off - it was PC manufacturers who kept adding more and weird keys (media keys, for example).

All I remember is having all sorts of fun trying to get those keys to work at all in Linux; they often were insanely setup and dependent on windows drivers (some would send a combination keystroke, some wouldn't work unless polled, etc).