Hello @nopasswords 
Going to brave://settings/clearBrowserData you see 3 options: Basic, Advanced and On Exit.
In none of them will it be selected by default to delete passwords, autofill form data, shield settings and app data.
When it is necessary to consciously click on the box to choose to delete this data, it is not necessary to have a pop-up to confirm again.
If you dont use a Sync chain, a password manager (like Proton Pass, Bitwarden…) or have backups, you lost this data.
Sorry for this 
Sync can save your passwords on chain.
How to backup: