The track did look great in GPL, no doubt. Back then tracks usually were just a big old ribbon, with a flattish plane underneath, and a distant skybox, all of which combined to look great at the time. When it was converted over to rF1, a ton of work was put into fleshing it out and hiding a lot more of the "simplicity" of the original GPL construction (simplicity being a relative term, it was a truly monumental piece of work from some very talented guys).
Now in the newer sims though, with much higher resolutions, DX11, etc the way the track is, simply looks too basic and simple. Considering the kind of guys we have now making the most astonishing tracks, fully built out into the distance, all beautifully texture mapped, TF now looks very, very old. Huge swathes of flat polys with one coloured obviously tiled grass, very angular surfaces and rectangular blocks for hedges. Massive holes in the scenery, and that big long ribbon of road floating off in the distance not attached to anything. The recent reduction that was made to the distance you could draw far objects in AC (probably to standardise things a bit more for the underpowered consoles) means that even the simplistic background mesh with the hills and mountains won`t work anymore. It just appears and disappears at will, leaving you with nothing but that long floating ribbon of road and some TSOs hovering in space.
It is a shame really, but without a monumental rebuild (perhaps even scratch) it will never look anywhere near as good as it deserves to.
