yes, I used Outlook desktop for both work (2 O365 accounts with different organizations) and personal email (multiple gmail accounts). With a job change, I am no longer on O365 (new company uses hosted gmail), but I understand there is a plugin for Thunderbird to work with O365.
I much prefer having the same client for all my email accounts, and Outlook worked for that purpose. It was better for O365 calendaring within the office, but it did not play well with google calendar. Thunderbird plays well with both (with a plugin for O365).
