Before Covid - rush hour was slow due to heavy volume. Now during covid traffic volume is low and I’d say the average speed is north of 70 with at least 20% doing greater then 85. I usually stay under 75.
I had an interesting observation a few years ago while on a road trip. In the nearby big city, there was a construction project (that lasted well over a decade) on the interstate loop where the speed limit was reduced to 45 mph but the average speed was around 75, even when workers were present.
But while in several western states with 75mph speed limits, there were no reduced speed limits in construction zones, yet the traffic would slow down to around 45 mph, even with all lanes open, but only when workers were actively doing something.
Lately the nearby big city has stopped reducing the speed limit in construction zones but the fines double when workers present signs are still out. Oddly when workers are present, drivers slow down from the posted 65 (actual 75) to around 55. Go figure. But the county road project did lower the speed limit from 55 to 45, no passing but I have been passed when I was doing 60.