I don't know the whole history of btrfs (although its primary maintainer was I think at Oracle at one point) but ZFS was definitely built from a hierarchical st

I don't know the whole history of btrfs (although its primary maintainer was I think at Oracle at one point) but ZFS was definitely built from a hierarchical storage enterprise mindset. Given different historical circumstances, it could probably have picked up more traction. But not sure what would change today even with an Oracle licensing change.