Same reason R* usually downgrades their single player games.. their damn Multiplayer modes.
It's the most infuriating shit ever, especially when downgrades get later ported on more powerful machines.
@SkyHighTrees Add draw distance and AO to the list, massive difference for both.
AO difference is absolutely awful for characters especially:
But in general game had a unique pre-rendered quality thanks to it which is not there anymore.
And what's worse to me is draw distance, as you said LOD management was jaw dropping in 1.00 with practically non-existent pop-in, when any version after display tons of missing trees/shadows all over the place.
I mean look behind the characters, it's insane: