That little term is a rebrand of working to rule. It's a labor action been around for a long time where employees work exactly to the terms of their contract and that's why it's getting rebranded. Working to rule is a much harder term to criticize.
Anytime “quiet quitting” is brought up, shut that shit down immediately. We need to undo this particular rebrand as best we can. Doing more than what you're hired for needs to stop, and it can't while people working to rule are being vilified.