This doesn't make much sense. "Interesting business conversations" should map 1-to-1 with microservices but also each microservice must perform a "simple, idemp

This doesn't make much sense. "Interesting business conversations" should map 1-to-1 with microservices but also each microservice must perform a "simple, idempotent business task" but also microservices can't be coupled to a database? Okay, enjoy developing your business with no data persistence whatsoever and where your architectural principles forbid you from ever so much as sending an email.