When they do, the WTS usually loses the case and/or (as in the McFree case) drop it.
That is for the Courts to adjudicate but any owner of a copyright is within his legal right to defend it. Don’t like it, too bad.
This is, effectively, a misuse of the legal system.
You can pursue that claim legally except that there is no law that says that it is abuse of process. For example SCOTUS decided not too long ago that police are within their authority to run anybody’s plates for any reason they like. The decision stemmed from a complaint in lower Courts that rogue police were getting personal information from the plates and selling it. The legal issue was whether or not running plates requires the standard of arguable reasonable suspicion. Court decided that they don’t need any legal grounds to do it. Many other examples. The principle here is that wt owns the copyright and at any point in a lawsuit they can legally drop it. And that is the law. Don’t like it? Write to congress for example.