The route that's being claimed as a link doesn't function as such in practice. Most drivers, especially of anything higher than pickup truck would take as the major corridor I-70 west to SR 79 coming up to Newark.

Currently mapping applications route on I-70 to exit 142, then US 40 (4 lane road with speeds approaching the interstate), then taking Linnville up to the city limits.

There is no special designation by a higher authority to give it backing either, like SR 16 with the NHS or SR 32 a few counties south with the Appalachian corridor, etc etc. Ohio's TIMS even argues for it being lower as well, labeling it as "Minor Arterial", which roughly correlates with the Primary class OSM-wise.

It does serve a function to connect the two cities as mentioned, but not direct enough for a trunk designation.