If I contribute my code to an open source project, then I - as the copyright holder - agree to license my work under an open licence.
If I use an OSS project, I am using other people's copyrighted work under an open licence from them. Without that licence, I have no legal basis on which to use that work.
Only real people can (currently) hold copyright. If person X writes some code, but the licence (incorrectly) attributes the copyright to person Y, and person Y purports to give me an open licence to use that work, then - crucially - I have no license from the actual copyright holder (person X) to use their work.
Until an effective open source license is made, this code is not open source; it is completely proprietary. If person X chooses to sue you for copyright infringement, it is no defence to say that you're using it under a license from person Y, because person Y had no right to give you that licence.
This is a major ethical and legal problem. I would be very wary of the Asahi codebase.
As I said, very weird hangup to have, definitely not motivated by other reasons.
Nor can anyone else, copyright is not generally 'destructible'. That's why it's a licence. The holder keeps the copyright, but licenses the work to the general public. (Assignments are another way to achieve something like this, provided the assignee then licenses the work.)
I assume what you're referring to is inalienable moral rights - hence the reference to Germany - but those are a feature of many (most?) of the world's legal systems. They are included in one of the revisions to the Berne Convention, if I recall correctly, which is an international treaty on intellectual property.
I understand you're sceptical, but the legal dimension of OSS does matter. Using copyrighted material without a licence would constitute a major business risk. I would appreciate it if you could kindly refrain from making ungenerous assumptions about the intentions of others.