pdftk was removed from Fedora linux because of itext5 license issues (https://lists.fedoraproject.org/pipermail/devel/2014-March/1...).
https://lists.fedoraproject.org/pipermail/legal/2011-June/00...
Which explains some more.
Ie: There is additional restrictions added to the AGPLv3 license in this specific case. The license allow fedora to remove them, but Fedora chooses not to do so.