The German copyright law doesn't seem unnecessarily vague, simply life+70 years, which is why there are now two authors blocked (3 at the time of the link). If you have a problem with Germany's life+70 years then you shouldn't be upset with the lawyers, you should be upset with your government to change your government's copyright laws to match whatever the US does.
It's a bit more complicated: The US adopted[1] the international regimen (life + 70) with an exception that US statute of limitations from before 1978 continue to apply to works published in the US before 1978.
So the US adopted everybody else's rules but has an escape hatch for older works - that only applies in the US and this is where the contention over these 3-5 works comes from.
The US later extended the "70 years" rule for anonymous, pseudonymous and work-for-hire works to cover 95 years since publication or 120 years since creation (whatever happens first) because The Mouse squeaked[2].
At least in this case the US copied Europe with it's term extensions (Disney certainly weren't unhappy about it but the notion that Disney drove this is a bit of a myth). And Europe set that term length when the EU unified terms because it set it at the longest length from the member nations at the time, which was Germany's life+70 years.
It's pretty interesting but the current global norm for copyright duration is, due to circumstance, almost entirely based on German norms.
