That's the thing. Just by glancing at the API docs, Windows looks more complicated but where the rubber meets the road in terms of real high-performance application development, Windows is way simpler. In Windows you can do in one syscall what would take several in Linux. You can schedule I/O calls across multiple threads in a completely thread-safe manner without having to manage the synchronization yourself -- and since threads go to sleep entirely while waiting for I/O operations to complete, there is no chewing up CPU cycles in a select/epoll loop. So yes, writing "hello world" or simple filters is simpler in Unix -- but writing multithreaded server applications that maximize throughput is simpler in Windows.

Unix is bristling with features designed to "allow you to save me some time". It was designed to make it easy to write quick, "one-off" programs in C. VMS -- the predecessor to Windows NT -- was designed to run long-lasting, high-performance, high-reliability business applications for real users with money on the line (i.e., not just hackers) and Windows NT inherits this legacy.