Most Android phones are already so locked down and partly proprietary that it's a right pain to meaningfully modify anything without jumping through tons of hoo

Most Android phones are already so locked down and partly proprietary that it's a right pain to meaningfully modify anything without jumping through tons of hoops. In short, I don't think it would have made much of a difference. "GPL vs BSD" is an old debate that's been done a million times, and I never seen any convincing argument one way or the other. Plus there's long been copyleft (GPL, CDDL) parts to many BSD systems, both in userspace and kernel.