"It really seems like anyone with some renders and a white paper written by someone being gassed up by an overly agreeable AI can get VC funding these days."
You have two options for shielding, one is shield the entire thing like we do with the ISS because people live there and radiation is bad for living cells. Two is to shield the smallest unitary entities to use the least amout of materials, like a shield per chip. This is physics not magic, radiation does not just go away. When everything add to launch weight it does not make sense. Redundancy systems also add to launch weight.
You have two options for shielding, one is shield the entire thing like we do with the ISS because people live there and radiation is bad for living cells. Two is to shield the smallest unitary entities to use the least amout of materials, like a shield per chip. This is physics not magic, radiation does not just go away. When everything add to launch weight it does not make sense. Redundancy systems also add to launch weight.