I mean, in 26 years in the industry I’ve never worked anywhere that kept ads up for jobs that had already been filled. Not even on their own websites where hosting those ads is effectively free (as opposed to LinkedIn et al where you have to pay).

I’m not saying there are no companies that keep non-live job ads up purely for fishing purposes but, in my experience, it’s not the norm. It would really piss jobseekers off and that’s the kind of word that tends to get around and make it harder to hire in future. Maybe not if you’re a FAANG, because so many people want to work for you anyway, but it’s going to cause problems for “normal” companies.