What you call "quiet quitting" IS putting in the work. You even said it yourself - it's doing exactly what is expected of you.
What you call "showing initiative" is allowing yourself to be ruled by the whims of a wannabe master. If they wanted you to do more, they should have put that in the job description. And if there's still work to be done, they should have hired another person. 1 can't do the work of 2.