Wet Weather

I have always found the wet weather to be way way off in every game. IRL lap times are like 20-30 seconds slower, sometimes more, yet they never seem to be more than 10 seconds slower in any CM / EA game made. I remember the old Geoff Crammond games, which I think has always been the best wet weather simulation produced. It could wet at certain spots, and totally dry in other parts of the track, and when it stopped raining, there was an actual dry line and it was still super wet off of it. 

i just can’t understand how; after 20 or more years and technology and hardware advancing so much since then, no one seems to be able to / replicate this sort of weather behaviour.