Pub/Sub is feature-equivalent to SQS. There are improvements (e.g. gRPC, better performance), but it's still a basic topic/subscription system with a very simple model; for example, just like SQS, it doesn't support fanout.

Is S3's queryability fixed? Are you referring to the Inventory service or Athana? Because the former is just a big CSV file generated daily, and the second is for querying content. You still can't query the inventory of objects (e.g. find all objects created yesterday whose key contains the letter "x").

Okay, with S3 I was referring to Athena.

SQS is a "Simple Queue", Pub/Sub is not. There are no topics in SQS, just distinct queues. There is no 1-to-many. There is no push. And so on...

SNS is Amazon's push notification service and any number of queue's can subscribe to an SNS topic for 1-to-many.