Outlook, Outlook Calendar, Teams, SharePoint... I'm honestly baffled by how bad they are. It's like it was made by aliens who only sort of understand what human beings want. And, of course, Microsoft is super selective about their product managers and pays them a ton of money--even though a golden retriever could have come up with a better UX. Literally all they had to do was fucking copy Google.
I think Outlook edges out gmail in a few ways like searching, multiple accounts, offline archiving, and maybe a couple of other things that I can’t remember.