What the … ??
I assume you’re salting and hashing my password… so why the f$@k are you restricting me to 16 characters?!
As public figures have a duty to lead by example and be better than the minimum baseline ethical standard humans should adhere to, so Microsoft have a duty to lead security best practise above the minimum baseline, and that includes not imposing artificial limits that reduce security. Bravo! Now fix it.