How is this more secure? They say "with a fingerprint, a face scan or a screen lock PIN", but basically all phones let you fall back to PINs if you dont want to do face or fingerprints. Pins are flat out not secure - typically just 4 digits. Yeah its probably better than 80% of people having "password123", but it seems strictly worse than a password + password manager? Or at least just having proper 2FA.
You enter a pin, the web server sees a public key that only your side has the private key to.