Not sure about there but here it seems it was technolgy. The more tech the late models bought the more they pressured promotors to get the track glassy and smoth to get maximun return on their investment. And the Modifieds have followed suit. Any kind of cushion is prohibited and every effort is made to not let one develop.
Promoters in this area only through enough water a few hours before racing on a track they have pounded to death all week to get some wheelspin to get the track blackened off as quick as possable. there are times it takes rubber before hot laps are done.
The result is when the traveling sprint car group in this area is on the card they can only basically idle the turns and try to drag race the straights. Or occasionally run single file on a rubbered down track.
Hard to get new sprint fans with that.

We are probably only the only area where race fans pray it rains pretty good the morning of race day. It takes a few hours of rain to soften the hardpan and get any moisture in the track.