Why did Android not use GNU?

Does anybody know the technical history of Android? Why did the project not go with GNU and attempt to make a touchscreen window manager and touchscreen applications on it (a mobile distribution if you will)? Maybe there are good technical reasons they didn't do it and went for a JVM stack instead. I'm thinking of linux phones (cheering for them) and just wondering at the technical history of android and if there's something valuable there. See: https://mindsgrid.com/google-choose-java-programming-language-android/amp/