It doesn't have to be good. What matters is that near peer adversaries see these developments and spend some of their resources on trying on R&D efforts to match ours. An arms race is a non-kinetic way to weaken your enemies before hostilities start. Unfortunately, AK-47s are cheap to produce at scale and our enemies have millions of people to give them to, so regardless of the fancy toys, the military still needs ammo, mines, grenades, rockets, bombs, and napalm to disable enemy soldiers at scale.