I was just providing an illustrative example, the exact implementation details are irrelevant. Android phones have been used as the central processors for a number of CubeSAT missions so without any circuit design you can get a sub $500 CPU kit which is much faster and cheaper than a $100k RAD CPU (and available at any electronics store unlike single board CPU modules).

Telecom satellites already require tons of specialised integrated circuits because general purpose CPUs are too complex and power hungry for the amount of bandwidth the satellites process. This SpaceX constellation will certainly have custom designed electronics, even if they don't use any rad hardened ICs.