I'll explain.
While GT5 doesn't model things properly like the tyre model (no temperatures, pressure, different segments, etc.), has a simplified suspension model (e.g. simplified springs/dampers, no caster, no bump stop, no positive camber), no brake physics (e.g. modeled fade/temperatures), dumbed down online physics, exaggerated draft, etc. etc.
it still manages to capture the real-life feel of the cars. E.g. when I get into a 350Z, it pretty much feels like the one I owned in real life. Same applies to other cars I have driven and/or owned.
There are other games out there that model all the things I mentioned, but still don't manage to capture the real-life feel of the car. :