> What the chardet maintainers have done here is legally very irresponsible.
Perhaps the maintainer wants to force the issue?
> Any downstream user of the library is at risk of the license switching from underneath them.
Checking the license of the transitive closure of your dependencies is table stakes for using them.
The problem is that the transitive closure isn't clear here. One of the entries is being claimed to be one thing but might in fact turn out to be another.
> Perhaps the maintainer wants to force the issue?
I doubt it, and I don't see any evidence that's what they're doing. There are probably better ways, if that's what they want.
> Checking the license of the transitive closure of your dependencies is table stakes for using them.
Checking the license of the transitive closure of your dependencies is only feasible when the library authors behave responsibly.