I wanted to love Thunderbird, used it for years then a bug [0] literally deleted all my emails. I regularly see updates of people understandably raging on the ticket :( It's a bug that literally deletes user data from both the server and the client without warning. It's been open and confirmed for 17 years straight. It could happen to you. How is it not top 1 priority to fix it?
[0] https://bugzilla.mozilla.org/show_bug.cgi?id=462156