So - high level summary - according to Working Title, the only way a plane can use the old Asobo Code is if it’s still pointing to the legacy AS1000. By extension, the Aero Files CommonBloom31 is pointing too, will also override the AS1000 code, and you get that improved version (but still not NXi).
If you’re using it for training or other experiences, it is missing all the base G1000 (non-NXi) functionality, no matter which version you use (Asobo or the Aero package). Not sure if that influences the desire to use that version.
I’m not aware of any current plane, stock or third-party, still pointing to the old AS1000 code, but anything’s possible if you know how to recode it I suppose.