Comment by hyperion2010

It's not that it is hard, it is that there are literally thousands of contributors that have contributed code under a gplv2 license that would have to be hunted down and consulted about any license change. I'm sure if you're up for it they would be happy to have someone give it a shot so that if a re-license was needed in the future they could do it, but right now there is simply no way to legally re-license the code without spending thousands of hours getting people to sign little pieces of paper that could be used improving the kernel (zfs or no).