Even if you update your Windows settings to say the new correct time zone, it still doesn't go back and update the time zone that future Outlook meetings are scheduled for.
I noticed that my personal calendar on my phone seemed fine, and iOS seems to book meetings based on a TZ identifier (America/Edmonton) rather than offset or a name like 'Mountain Time.' That system seems to have worked well in this case.
It's tricky, do you want future meetings to follow the city they're in, or do you want past meetings to properly track when they happened across zone redefinition (and what even is correct)? There's no simple way to get this right everywhere.
I still think the path Outlook took wasn't ideal for the majority of their customers in the effected places though.