actually no, a big part of the GPL3 these days is fighting "tivoization" which is not really protected by any "system" the same way as copyright. the only system protecting that is a cryptosystem locking it to manufacturer-authorized stuff.

also GPL is mostly trying to fight closed-source code which is just as possible without the current copyright system, it can still be kept private like any trade secret. GPL relies on the system to force releasing source.