Cause they were selling stadia. It didn't need to support general purpose, they were not looking to sell the controller for general use (google terrible at har

Cause they were selling stadia. It didn't need to support general purpose, they were not looking to sell the controller for general use (google terrible at hardware support). People buying it knew it only worked with stadia. For stadia use, it made sense and connectivity over Bluetooth would have increased latency and complexity to the cloud service. Moot point now, but atleast they opening it up so you don't have to throw the hardware in the trash