The worst thing about the new Outlook app was how Microsoft stuffed actual ads into it. And not like "hey check out this app that the devs totally didn't pay us to promote! 👀" ads, I mean actual, full-on promoting garbage and junk ads. Worse, they made it look like email messages too. URGH.
With the TBSync and the Exchange ActiveSync Provider extensions updated for the latest Thunderbird versions I can now also access all my Outlook services in Thunderbird too.