is it possible to reset 'To Do' for a user account? i want to start using 'To Do' with my work account like i do with my home account, but when i sign in to To Do, i see a lot of old tasks that seem like they are coming from either my Windows 10 work client, or my Outlook 2019 client or maybe even Cortana on my work client? I'd like to wipe all that out (dont need it) but i want to leave all the stuff Microsoft builds in to a new account (default lists & settings). Is there a way to do this?
Sounds like it might be taking tasks from other apps you use on your work account - try to remove them from settings if you've not done so already.
In terms of a factory reset - I'm not sure it's possible as you envisage it. I think Microsoft see's To Do as a central repository of tasks so it will by design try and grab data from where it can because it believes it's being helpful that way.