Need some non holiday time to read this fully, but it's worth noting that aside from Spanner, Cloud Datastore (using Megastore tech) and Cloud Firestore (using the same tech as Cloud Spanner) all do Paxos across several data centers over a wide area and achieve millions non batched writes/second.

Sometimes it can be hard to tease out the true trade-offs in the systems as they don't get as detailed acknowledgement, but from a quick read it looks like tail latency will will be worse.

Improvements in consensus algos often have issues, correct implementation is hard, but it can make previously impossible things tenable which I find exciting.