To prevent wall messages from messing up all of your open terminals:

sudo systemctl stop systemd-ask-password-wall.service
sudo systemctl stop systemd-ask-password-wall.path

To make this change persistent over boot:

sudo systemctl mask systemd-ask-password-wall.service
sudo systemctl mask systemd-ask-password-wall.path

Ref: https://unix.stackexchange.com/questions/382272/systemd-ask-password-only-prompt-on-current-console