The chassis sizing of the G70 is quite logical for a 2 door variant of the G70. The reality and question is what does it cost to R&D, tool and design everything for the sheet metal on a 2 door? Usually 2 door cars have unique seats (to allow for rear seat access), most interior bits are different less the dash. It sounds like a lot of investment for not a lot of vehicles sold.
I guess this is why coupe versions of the sedan (Like Infiniti Q60 Coupe vs. Q50 Sedan) cost so much more, trying to recoup the R&D and tooling to make the lesser sold variant (amortization over fewer sales).
