Chain Replication (and friends) are vastly simpler than Paxos (and friends) in many ways, but do have the same requirement for determinism. That's because chain replicated systems typically need to be confluent (see https://pathelland.substack.com/p/dont-get-stuck-in-the-con-...), which means that all the replicas need to have the same value in them when replication is done. Conceptually simpler, for sure, but many of the same challenges remain.