And it was gratious cruelty from NATO to destroy the pipes fabrication plant during the first Libyan civil war.
You're also assuming that the GMMR would not have been commissioned by another Libyan government, and perhaps even been completed more efficiently, had Gaddafi not seized power and held onto it for decades.
While NATO's bombing of the Brega plant was controversial, it was in my view justified by Gaddafi's forces staging rocket launchers at the location. If you're staging active military assets inside civilian locations, and they're part of hostilities, those locations lose their protection under international law.
The Brega plant was also not critical to the ongoing operation of the GMMR, as there was a second plant at Sarir that was able to make the pipe sections and had sufficient capacity to handle maintenance and sustainment needs.