Thought-terminating cliché
A thought-terminating cliché is a form of loaded language – often passing as folk wisdom – intended to end an argument and bypass cognitive dissonance with a cliché rather than a point. Some such clichés are not inherently terminating and only become so when used to intentionally dismiss dissent or justify fallacies.
Source: Wikipedia — Thought-terminating cliché (CC BY-SA 4.0)