Password managers are absolutely not required. While they're a good idea for most of us who don't have to worry about having somewhere to sleep, homeless people can still most likely memorize a password and remember it after a few tries. They can't do that if 2FA is forced on them.
Everybody sucks at memorizing unique passwords. I'd be stunned if homeless people are consistently not reusing passwords. Credential stuffing is the #1 form of account takeover and 2FA is the solution.
