I encountered the same issue on Windows 11 (Brave version: 1.31.91) and managed to solve it by turning off the automatic proxy detection in the windows settings:
- Open Brave and navigate to Additional Settings → System
- Click on “Open your computer’s proxy settings” (Windows proxy settings are opened)
- Turn off the automatic proxy settings detection
- Restart Brave
- Open a new private window with Tor
- Tor starts initializing - et voilà!