I totally missed this part of Microsoft Office #enshitification
- AutoSave is only available if you have an active Microsoft 365 subscription.
- AutoSave only applies to Microsoft 365 files stored in OneDrive
https://support.microsoft.com/en-us/office/how-do-i-turn-on-autosave-dbd19b49-ff3a-48f5-8294-671e33a6712c
And people still pay money for this steaming pile of garbage?