I'm sure GT7 will have the other titles beat in sheer number of premium cars but the problem is the majority of those premium cars will be old cars while the other titles will have much more of the current cars as was the case from GT5 on.
Where is the Huracan, 458 Speciale, FF, 599xx, Viper (TA, GTLM, GT3R), newer BMW (M5, X5/6, I8), McLaren (P1, newer MP4, MP4 GT3), newer Ford Mustangs, newer Chevy Camaro, newest Chevy Z06 Vette, Nismo 370 Z, Alfa 4C, Audi (S8, RS3/4/6, A7/S7), Mercedes newer sedans and coupes, newer Cadilac offerings, Dodge Hellcats the list goes on and on. Some of the cars I mentioned came out this year so not likely to see them in there this soon but the majority I mentioned were already out a few years and yet still not in GT6.
My wish is for GT7 to be more current in premium model lineup and have a better system of adding up to date content.