In theory maybe, but in reality, on a muddy, dusty, or wet, salty, or gritty battlespace, maintenance is very important. I'm retired with over 20 years of military maintenance and logistics. The more complicated the electronics, the more things that can go wrong. With robotics, that tends to go up exponentially. Murphy's law.
Now I say all that, but there have been some amazing advancements in redundant circuitry. I worked with what we called SRUs and LRUs (Shop and Line Replaceable Units). We were beginning to see advancements where if a circuit card failed in the field, on a mission, a spare circuit card in the 'box' could be reprogrammed using FPGA technology. Without boring you with too much detail, it was pretty amazing stuff. 20 circuit cards in a 'black box', 15 were duplicates and programmed on the fly.
Mechanical parts, not so easy to make redundant I would imagine though.