I can confirm the one-way tagging is correct. It used to be two-way, and was converted to one-way, using dinner, and lightweight barriers. I'm not sure, but I suspect that there were too many car crashes here when it was two way.

As for whether a motorway_link tag is best, I'm not sure. But I can say on the ground it feels like a motorway_link, with busy highways at both ends, and generally dismal surroundings. 

I'm not sure if that is enough to resolve this note, but I hope it's helpful.