Nvidia has done it before, gtx1060 for example
I don't think that is correct in regards to the 1060. It was always going to have 2 cards and the latter was always going to have more ram. I believe this 3080 super is just a response to the market and was never originally intended. They are trying to squeeze consumers.
Nvidia normally has 2 cards in every tier and they sometimes also do a revision.
1050 and 1050 ti second has more ram
1060 3gb and 1060 6gb should have been called 1060 ti
1070 and 1070 ti
1080 and 1080ti the second has more ram
They also released for example a 2070 then a 2070 super later on. This is normal.
1600 series originally had
1650, 1650ti, 1660 and 1660ti.
They later released 1650 super and 1660 super.
The 1060 6GB was always intended just delayed. It's nothing like supers which have tended to be revisions.