According to Sean Davis at The Federalist the new regulations are nothing more than retaliation against Defense Distributed:

On June 3, just four weeks after Defense Distributed filed its complaint in federal court, the State Department suddenly decided to propose a new rule giving it the authority to pre-approve speech related to publicly available firearm plans. The State Department’s play here is obvious: it hopes to promulgate a new rule making its previous anti-speech efforts superficially legal in order to short-circuit Defense Distributed’s court case. If that were to happen, the non-profit would then have to file a new and separate suit alleging the unconstitutionality of the new rule.