I mean, Polyphony is as obsessed with the graphical representation of vegetation and trees as some of the forum posts here. I remember PD mentioned swaying trees in the wind and reproducing accurate tree barks when GTSport's detail page first went up on the official GT site. Vegetation and trees make up the majority of the tracks, it's extremely noticeable when they look unrealistic compared to everything else. Even if you're zooming past them, you were still looking dead at them in front of you at some point. And photomode is a huge part of these games that poor vegetation will pretty much ruin any good pics that are shooting for realism.
"Landscape
Huge strides have also been made in landscape expressions. See each and every leaf on a tree as it sways in the wind. Weather, time, and the age of the tree are considered when reproducing it in the game, right down to its bark. Even the asphalt possesses unique characters, regarding its size, grain and distribution of the asphalt surface. Thanks to advanced data capturing and the perceptional talents of the artists, Gran Turismo approaches landscape reproduction from every aspect."
We never got swaying trees but at least we know it was a goal at one point. Most of the roadside trees on Nurburgring have nice detail, and tree stumps and branches were actually 3D with various multiple different 2D cards making the leaf canopies (same approach as Driveclub), unlike tracks like Alsace, Brands Hatch, Red Bull Ring where an entire tree, or even row of trees, is made up of one large single spinning 2D card that doesn't even light or shade properly. The difference in quality is so stark you can tell which tracks Polyphony rushed through in development either from running out of time, lack of manpower, or both. They should really start getting some outsource help for track assets too.
Nurburgring
Alsace
Red Bull Ring