While I understand the intent, I feel that is much less rigorous than the 2 problems mentioned ("You Cannot Have Exactly-Once Delivery", and CAP), both deal wit

While I understand the intent, I feel that is much less rigorous than the 2 problems mentioned ("You Cannot Have Exactly-Once Delivery", and CAP), both deal with the fact the network is unreliable and only that - even if you had unlimited RAM and disk, the two proofs would still hold. Here a possible solution is proposed "Send the message to Bob even if Carol is offline and store the message to Carol for later delivery.", and is really just handwaved away by saying no one has unlimited disk space (or a 24/7 ops team) (also doesn't Amazon sort of solve this problem?). I'm sure that is a practical limitation, but for the sake of building reliable systems I'm unsure its strong one. If thats the case, then one could also argue Raft also isn't linearizable, because the replicated log file could get really large and no one has unlimited disk space.