I'm stuck at the "just vibes" level but as I've watched new roads being built in the area, there's gotta be something about "nobody fucking planning anything" and just sticking shit wherever they can legally do it.

So people needing to get around a town are driving on the same roads and routs as people who are trying to commute to work 40 minutes away and semi-trucks pulling a 60 foot trailer and somebody driving a tractor with a brush hog to a neighboring field.

When you've gotta travel farther you start to get anxiety that you're going to be late for work or appointments. Leaving earlier doesn't help as everybody else starts leaving earlier and increases stress as that means you're doing everything earlier (waking up, getting kids outta bed and taken care of, eating breakfast, getting yourself ready to leave, etc).

So even though a reduction in the speed limit makes perfect sense and would absolutely not slow down anybody to the point of being late for anything, as has been mentioned several times in the comments, we're so car brained in the west that anything that would "slow us down" amps up the anxiety that we're not going to get to where we're going in time.