Only by a linear factor. Current OpenZFS is no longer the Sun released ZFSv28 code of old. Oracle does not have the copyright for these important, non-trivial parts.
If the point of the SFC is that those 10 years of non-Oracle/SUN development can be ignored, than on the same basis all the extensions to Linus' code can be ignored as well and he can simply relicense. But that is not something they want to argue, since they rely on ownership transference of some of those parts.
