Thank you, that is helpful. I mentioned this in another comment, but an issue that I have run into before is where an institutional outlook email would not connect to Thunderbird. It seemed to be an issue around them not enabling IMAP on their side but I couldn't understand why I was able to get the email added to Thunderbird and go through 2FA , but the account still would not sync.

I'm not expecting you to act as tech support! Just using this example to demonstrate the type of problem I experienced that made me want to better understand how email works.