> If the BSD distributions hadn't run into problems relating to legal battles at the time, Android would be built on Mach with a BSD userland rather than Linux.

What legal battles were there? Wikipedia puts Android being started in 2003 [0] and then only legal battle I recall with BSD having settled in 1994 [1].

[0] https://en.wikipedia.org/wiki/Android_version_history

[1] https://en.wikipedia.org/wiki/UNIX_System_Laboratories,_Inc.....