Quite clearly what the plaintiffs are afraid of is that there are a few very popular works in there that they could be making real money from. There's no way to know this from the mean alone.
The companies have very successful legal departments. They go after the next lowest hanging fruit. They are just working, it's their job description to do this. This is why they will never stop, it never gets too absurd or overly unreasonable.
This was a good example:
https://rec.music.theory.narkive.com/y829eFoE/metallica-want... > Metallica are taking legal action against independant Canadian rock band Unfaith over what they feel is unsanctioned usage of two chords the band has been using since 1982 : E and F.
and:
> > We're not saying we own the E chord, or even the F - that would be ridiculous. We're just saying that together, people have grown to associate them with our music, and their continued use in the same song causes confusion, deception and mistake in the minds of the public.
The lawyers are simply aggressively[sic] exploring the limits of the law. They are not afraid to lose money if you play the E and F chord but it would be a nice victory if you couldn't.
In this IA case they are exploring a total shut down. I'm sure it again includes many works they don't even own the rights to. It seems equally sensible (or senseless) to fine and ban people from holding copyrights after repeatedly filling illegitimate take down notices.
Who knows, we might in stead end up auctioning the frequencies like with radio.
You might have a few hotspots, but there's a very tight upper bound on how many downloads of each item. Further, it argues that the overall collection has a very high research and preservation value compared to the total number of downloads.