While I agree about your core point (star schema ETL is great at most DW use cases due to simplicity and breadth of roles supported), I fail to understand how c

While I agree about your core point (star schema ETL is great at most DW use cases due to simplicity and breadth of roles supported), I fail to understand how columnar stores are any more difficult to work with. My team routinely joins over trillions of records using standard SQL queries without any issue, all the map-reduce happens behind the scenes. In fact, it has been so successful for us that we have replaced almost all of our historical ETL infrastructure based on Spark with a single columnar store; while infrastructure costs have gone up (generally the price to pay for generalization), we have gained a great deal of human efficiency and DW maintainability.