I didn’t read the whole thing - but I would think an interstate would be designed to go the speed limit and still be able to stop in time coming over a hill.
I was on a hilly, winding road in Oregon. The posted limit imho was about 10 mph faster than what I thought was safe - at least to be able to stop in time for a deer (it was twilight) standing in the road just beyond the curve or hill.
I usually go faster that the posted limit - so it was really odd. Of course every so often I had to find a driveway or wide spot to pull over for the person behind me.
I was lucky on that trip earlier on while on the interstate. A car was on the right shoulder up in the distance - rainy night. I was in the right lane, following a car, and I moved to the left. The car in the right lane swerved out of the way at the last minute to avoid a second car stopped in the right lane. He had plenty of room to swerve in front of me (I had slowed down just a bit), and hopefully I would have been able to react in time if I had still been in the right lane - but it sure spooked me.
My driving instructor in HS gave one bit of advise I remember to this day; to drive like everyone else is an idiot and trying to kill you. I gave same advice when I taught our sons to drive and so far it’s worked for them, too.