Those businesses have better things to do than piss off their customers and authors as they try to police the internet.
Even more cynically (and predicted by Max Headroom ~35 years ago) academic work has more potential to unlock economic value for the unwashed masses, so it needs to be better policed.
Scihub is completely different from Libgen in terms of ethics. No academic has ever written a manuscript for publication in a peer-reviewed journal because they were going to get paid for it. There is nothing whatsoever ethically problematic in accessing Elsevier's content on Scihub. Those journal articles should be free to the world, not least because the reasearch is often paid for by public funds.
Do not confuse what I'm saying. I am not saying that I think Libgen is a bad thing. I am saying it is a difficult area from a moral/ethical/economic point of view. Scihub and Libgen are the most fantastic libraries the world has ever known. Literally. It seems pretty clear that making them available to someone in rural Angola is a good thing to do. I work in a highly developed country and it's slightly less clear that the anarchy should extend to benefit me, but honestly I'm happy that it does.
Just to add my 0.02$ as a soon-to-be-phd-dropout, I once downloaded my own paper from SciHub after I lost the stupid PDF and of course the publisher wouldn't let me get it for free. If anyone plans to assemble a torch and pitchfork mob, by all means let me know.
The sentiment behind the downvotes might be something like, "The first rule of libgen is you don't talk about libgen."
If I ran HN, I'd require a brief comment to be associated with each downvote, but then I'd do a lot of stuff differently.