It seems to me there was something like that with old iMacs when booting in to Safe Boot, e.g., you couldn't enter your PW at the prompt because the bluetooth had not (yet) loaded. The solution was to hunt up a wired keyboard and then put things to right.
27" i7 iMac (10.13.6), iPhone Xs Max (12.1)
Those who can make you believe absurdities can make you commit atrocities. ~Voltaire