Many recruiters don't use jobs the way you expect. They're posting jobs as lead generation to fill up their ATS with candidates. They don't even necessarily care what job you applied to. However, they also primarily want active candidates, so they prefer to look at candidates that recently applies as it shows active intent. They repost jobs to get a new batch of active candidates to sort through.

Is this messed up and totally broken? Yes. Is it how many recruiters operate? Unfortunately, yes.