I'm a civil engineer, specifically geotechnical, who has done a lot of work in the area. PA isn't really special. Many PA roads were just built shitty, so they require more maintenance, which costs more money in the long run, which means money is drained on maintenance that could have been spent on actually building the roads right in the first place. All those other states have their own challenges when it comes to road construction. Go ahead and build a road in Delaware when groundwater is six inches below grade. See how easy that is. Just look at border transissions. The climate and terrain don't typically change because you are one mile or so either side of the state line. But road conditions definitely do.

We have built pretty good roads through much more adverse terrain and climate than you will find in PA. We've only been building paved roads for a few thousand years, but I'm pretty sure we can overcome the climate and terrain challenges offered by PA if it was done right from the start.