Silent quit is not as easy as people believe, silent quit means to switch your mind from “I can work hard as I love my job or wants to get promoted” to “will work what I'm paid for or i don't care if promoted or not”
People who is used to work harder will find way harder to stop working at this speed, and of course companies will notice when the guy/girl who used to do the work of 3 suddenly is just doing what they were hired to do and nothing more.
But the benefits are impressive, when you manage to switch your mind the stress will go down, also you won't care if the company is going down as long as you get your paycheck, and you will be able to negotiate more in case they ask you to do more work again.
Worst case scenario: “you won't get promoted”
Best: “less stress, and more freedom to follow what you wants”