Well, or it could be that the people that don't get responses are louder so we think they are lax and you are lucky. Xcode still sucks, despite all our bug reports, though, so I am inclined to believe they ignore most requests. (Were your bugs security-related?)
Yep- send bugs and feature requests to https://bugreport.apple.com/ . Everything gets read, eventually, by a real live person.
There’s more information available about reporting bugs (like which logs are useful, where to find them on your device, and how to get them off your device) at https://developer.apple.com/bug-reporting/ .