No confusion on second point. My argument was that Kafka adds significant complexity and delivery risk because it's software that you must run on hardware/VMs, rather than a fully-managed service. You have to pay a whole lot of eng time to make Kafka truly "guaranteed delivery" because there's always risk of underlying hardware/VM/LB dying.

Pubsub guarantees delivery regardless of what happens with underlying infrastructure. In a sense, the bar has been raised dramatically.