Don’t forget the super bug also replaced the A6 despite the fact that a rewinged A6 (A6F) would have been cheaper, have better range and payload, and still have an unmatched CEP in a N/AW environment.
The A-6G was a rewinged A-6E with some new electronics.
Either would have been good.
What the USN got were 20 A-6E with just the new wings, which were then scrapped before service.
All to justify aquisition of (in order), the A-12, the super stealth ATF, the F/A-18E/F.