Rick Houlihan has another talk from re:Invent 2018 where he goes into great detail about this -- see the following Twitter thread for a jumping off point.
I think this nicely illustrates why most projects shouldn't use a high-scalability NoSQL database: they benefit much more from flexible data models and efficient query.
All that being said, there are other factors when choosing a database aside from those three. For some of our microservices, my team doesn't need scalability or flexible queries, just efficiency. However, we've found that it is cheaper/easier for use to use DynamoDB than RDS.