Licensing is a problem for SOME formats. ZFS, ext4, and plenty of others used by BSDs and Linux distros have no licensing issues. Also, if any player cared to

Licensing is a problem for SOME formats. ZFS, ext4, and plenty of others used by BSDs and Linux distros have no licensing issues. Also, if any player cared to win the filesystem war, they'd open up their spec royalty-free.