This is the fundamental issue with networked storage: all apps on top assume small io is fast an local, so network latency doesn't amortize.

With application-level replication, you can amortize it to a few steps (e.g. on commit, do 2PC).

Obviously there's nuance, esp if you have to read from another node, but it's why moving replication as far up the stack as possible generally performs better with DBs -- the DB knows when to touch the network better than the disk.