Android won because they followed the Windows Mobile model of letting OEMs run the OS with their own hardware and UI flavor. The first successful Android device was the Motorola Droid which had a Blackberry/HTC-like hardware keyboard. Later devices like the Moto Atrix offered a desktop environment inside Android when hooked up to a monitor. This idea was later extended by Samsung with Dex Mode.
That is what OEMs wanted. They didn't want to be an interchangeable manufacturer competing on price, which is what happened to Windows PC makers.