So Facebook app is no longer preloaded, and so can be deleted (not just disabled or "uninstall updates) - can be totally removed.
But "Facebook services" and "Facebook app manager" is still forced and not removable - those can only be disabled and "uninstall updates".
I think "Facebook app manager" might have reenabled itself once too.
You also can't set battery usage to restricted - the options other than Unrestricted are greyed out.
So close yet so far.