Webkit's webauthn support is in development [0]. Hopefully the adoption will improve a lot once all major browsers support it.
You can test it right now with any recent Android smartphone with TPM chip:
Apple will eventually join the club too once they stop dragging their feet.
Of course with the TPM you effectively have a hardware token permantently physically linked to your smartphone, so it changes the security analysis a bit.
For users this means that WebAuthn for accessing websites on a TPM-capable smartphone is really just a matter of unlocking the device when prompted. Quite user friendly.