This article is kind of dramatic about describing a normal thing. Alpine highways everywhere in the world have to deal with this. The entire Mountain West is built for this, including some parts of California.
Maybe the Federal government has never bothered to invest in some aspects of road safety in Yosemite. That’s somewhat embarrassing. I’m surprised this is even an issue in Yosemite given how many other places have had this forever. Far more remote and unpopular highways have addressed this problem.
It is difficult to paint this as anything but incompetence.