Freely rotating bearing surfaces don't really offer much compatibility with multicellular life. For nutrient/waste transfer or nervous systems to work between an outer body and an axle-like thing would be a big evolutionary step! It's fun to ponder how it might work and whether it could work robustly. We have the same kind of obstacles with machines featuring freely rotating assemblies: tire pressure sensors have to wirelessly communicate. Steering wheels, on the other hand, support wired connectivity thanks to a flexible connection and limited range of motion similar to joints in animals.