And don't get me wrong, I'm probably one of the biggest enemies of
the term "intellectual property" in the open source context; for
companies it's another matter, however, we have to play by the
rules of the system and be clear about what we mean.
For lawyers, calling something "public domain" doesn't mean much
to them. So endure the pain, license it under BSD-0, so Google's
lawyers and future peoples' lawyers are happy and we actually get
shit done.
Or go the SQLite way and charge a fee to get an explicit license for companies that are not comfortable with Public Domain

http://sqlite.org/copyright.html

That's probably much stronger than the musl community would be comfortable with and also too late as it would require all past contributors to disclaim copyright, not just Rich but it's worth noting that public domain ideology is not incompatible with corporate use.