YubiKeys is a password manager in a dongle, thus the exact opposite of passwordless.
i ought to reword password to sustain my credibility, any publickeysignatures (PKS) are of course more unreplayable than presharedkeys (PSK) but call them token lengths rather than password lengths they are longer than zeroconf easy zero. as long as my system are not immune to an rm -rf / i will not null my own passwords but one day i will.