Just like GT3 and GT4 never came out, right ?
You're acting like this is the first time they do something like this.
Over the past decade, they have:
- made custom demos for auto shows for Nissan, Toyota, Lotus, BMW, etc.
- designed various liveries for racing teams
- developed multiple wings and other aerodynamic parts for NISMO
- developed a board computer for Nissan
- hosted their own awards show Gran Turismo Awards
- worked with Citroën on the design of a complete car
- been invited to judge the prestigious Pebble Beach Concours d'Elegance
etc.
Stuff like that is what separates them from all the other devs out there.