Mauro Gilli, a senior researcher in military technology at the Swiss Federal Institute of Technology (ETH Zurich), responded to Musk’s claims, pointing out the complexities of defence technology."What makes the F-35 or the B-21 expensive is the software and electronics, not the pilot per se ... which is important because a reusable drone would need to get all that flashy electronics of an F-35, which is expensive," Gilli wrote on X.