Again, Microsoft managed accounts!!! Microsoft has been pushing this on small to mid-size businesses. Our entire company's email is managed by Microsoft through Office 365 (now Microsoft 365) for Business. We are paying them a hefty amount because I see it in my operating budget for the teams that report to me.
I have deleted my email account and re-add the account, and am using the latest version of the client. Just to de-wrinkle one element, I even downloaded Outlook for Android, which is not my favorite, and it still has the same issue. And to put into context, I am a developer with in-depth knowledge, so please don't assume those of us haven't tried things you are suggesting.
I can tell you have very minimal experiences on this because with Microsoft-managed accounts, our in-house IT has very very very limited options in terms of infrastructure level settings or issues - they are ALL controlled by Microsoft.