That's what data warehouses are good for though. So long as you have something you can join on, you don't need to worry about how the application developers structure their systems.
Theoretically it's true (but again the burden is simple transferred to someone else).
But in reality, as a BI Developer (prev as a data analyst), what I really don't want to do is a join by timestamp (and a userId), pretty much the only way to join two "subsystems" that are not interconnected.
Example:
Analysts want to know what's the coin balance when player starts purchasing energy bundles. Now that they don't know about each other so the telemetry only has one common field: userId. Eventually either BI developer (who develops DWH/View/etc.) or DA has to write a join by userId and timestamp to get the most accurate coin balance when player purchases an energy bundle.
