When it comes to composition and length, passwords mostly don't matter
In my opinion, Microsoft's implementation of MFA on Office 365 (at least our instance) is broken. SMS MFA is inadequate and should not be used, the SS7 network is apparently trivially hackable in some circles and text messages can be rerouted. So they want us to use MS Authenticator, great. However the 365 login screen always has the "Sign in another way" option in which I can just bypass the Authenticator app and use an SMS text. I cannot remove my mobile number from my profile to disable the option to SMS text because they are worried about me losing access to my app. I don't know if this is a limitation of Office 365 through our VAR or what, but it just seems pointless to offer an Authenticator app if there's an easy way to fall back to SMS and no way to disable SMS. If someone has my password and can reroute my text messages, a fancy shmancy Authenticator app is pointless. If this is not how it is for others with 365 I would love to know that, I hope it's not a limitation or policy put in place by our VAR.