I think that the RHEL example is out-of-place, since IBM (“Red Hat”) is clearly exploiting a loophole of the GNU Public License. Similar loopholes have been later addressed by e.g. the AGPL and the GPLv3*, so I expect this one to be addressed too.
So perhaps, if the GPL is “not enough”, the solution might be more GPL.
*note that the license used by the kernel is GPLv2. Cue to Android (for all intents and purposes non-free software) using the kernel, but not the rest.