I don't necessarily disagree with the sort of thing they want to do, that definitely fits one kind of business model. But I wouldn't want to go to court the license as presented (and now entered into by some unknown number of people).
Like the LGPL is confusing because it is not written well in some sense. But that goes to "confusing" instead of "unenforceable".
But yes, better written the problem with this license would just be "They are trying to claim things they know they can't claim" instead of "they are actually claiming things they know they can't claim".
The next question that would pop into my head would then be "At what point does attempting to claim rights to things you know you can't, as a way of scaring people into paying you, cross into unfair and deceptive trade practices"
Additional question: if you can fix that problem with the contract with a "to the extent possible" predicate, is that really not the default? Like, if a clause can be interpreted as requiring the impossible, even if a straightforward alternate interpretation doesn't, that clause is broken?
In my experience, the lawyers mostly warned the clients and the clients did it anyway.
Part of being a lawyer is simultaneously taking the blame for stuff like that while having done very careful diligence so that your malpractice insurance rates don't go up from clients successfully suing you :)
