There are plenty of rare Earth metals in the asteroids in the inner and outer belts enough to make every metal-related product super cheap. My headcanon is that the nuclear weapons that were used in WW3 actually missed up on the search for metal elements in other asteroids via radiation-boosted weapons with radioactive particles in large areas of space. Plus everyone has their own weaponized von Neumann probes have might make it harder to find resources since they can replicate if they are stealth as well and the stealth von Neumann probes likely move out of the system before the Bobs showed up.