... and the reason that they want to do that is so that the person cannot collect benefits, or has a harder time doing so.

Maybe you've worked with better employers than I have, but it's pretty much been an open secret in a few different places I've worked, both inside and outside of tech.

Or, sometimes it's not a PIP, but something similar. Many fast food places have a policy where if you're underperforming, your hours get reduced. If they want to fire you, they don't fire you: they give you one, four-hour shift a week at the slowest possible time of the week. That way, they didn't fire you; you quit, and so you don't get unemployment, etc. If you don't show up for your shift, then you're fired with cause, and so you don't get unemployment, etc.