Sure, but the base_backup process is painful enough to make it non-trivial. It's not like you can just bring up a new postgres instance, point it at an existing

Sure, but the base_backup process is painful enough to make it non-trivial. It's not like you can just bring up a new postgres instance, point it at an existing primary and say "catch up and start replicating". Replication has certainly gotten much better in the past few years, though.