This is a great question! I think it is something that the platform can potentially address in the future via community inputs, e.g. people can report they have submitted to this position but never heard back within a week/few weeks. The more a position gets reported, the more indication that it is a ghost job. I am open for ideas here.

Sometimes, companies shift engineers whenever they can before layoffs, and sometimes, they let go folks to rehire or hire back folks that were laid off if rehire proves difficult. I am not sure why companies do this but have seem it happens.