This feature is still on the backlog.
Settings should be taken over from the regional settings of the user. These settings are important in an international context. These settings rightfully so are done on OS level and should not be tampered with in the application.
Please check “Teams/Skype Consumer chat and calling interop” on the public roadmap at microsoft.com/microsoft-365/roadmap?filters.. for updates.
We’re currently working on defining a compact mode experience. I will post more details when we have more to share.
Thanks for following our suggestion to vote this up on SharePoint. It worked! SharePoint has confirmed that they have already started working on this and I’ll be getting an ETA from them after the holidays. -Suphatra