Its fun to read and get a little insight.
Even though there are 800 cars in the game PD manages to make them have there own distinct feelings.
75% of racers out there seem like the cars are the same and they just have more or less points in handling, accel, speed, brake.... They all feel like the same car with more or less points. In GT its fun to drive each car since they all have there own quirks. Like the way AE86s have that unique fishtail to the way F1 cars stick all the turns in almost any gear.
There is actually a point to buying and trying out new cars. When you play other games its all the same. Just by car x, y or z cause they have the most points and will be at the front of the pack online. When you play GT online you get surprised by some of the cars that opponents manage to pass you in.
Another nice thing is that the cars still carry more or less the same feeling with them throughout other GT games. If you like car X in GT3 you will still like it in GT5P (if its even there lol).