I suspect BT is a major cause. Apple may want to make sure that the apple watch experience is at least as good as it is on iphone. So apple may be unwilling/una

I suspect BT is a major cause. Apple may want to make sure that the apple watch experience is at least as good as it is on iphone. So apple may be unwilling/unable to spend the resources to support every android device out there. And working in BT consumer products, yes, android bluetooth is still a shitshow and device-dependent. Each radio vendor and android device has its own quirks that take time and resources to account for. Apple has had a very tight leash on what its devices do for bluetooth.