Transpiling to `/raw-templates` is important so that they are detected by the `eager-load-raw-templates` initializer. Prior to 16c6ab86 this wasn't a problem because all connector modules were being eager-loaded. Now that connectors are lazily loaded, it's critical that `eager-load-raw-templates` does the eager loading. This problem doesn't affect themes because they compile raw templates into an iife instead of a `define()` module.
Unfortunately we don't have any way to introduce automated testing for this part of our compilation pipeline. However, discourse-calendar will begin depending on this functionality imminently, so its tests will warn us of future regressions.