No doubt Rochester's Inner Loop project has created many benefits: 1) removal of an unsightly sunken highway that divided neighborhoods; 2) restoration of land to the tax roles; 3) addition of bike lanes, parks, public open spaces and other improvements.
However, as you can see from the links you provided, the inner loop (while handy for those who knew how to use it) was not heavily trafficked. So there was really no "hit" to East-West (I-490) travelers bypassing the city. I-81, by contrast, is a major artery connecting Canada and the north country to PA and other points South (along with serving Syracuse suburbs). 481 is there, but it's pretty far to the East and doesn't seem configured to be a viable I-81 alternative.
Clearly, all New Yorkers have an interest in this issue, not just Syracuse residents. It appears that the "community grid" option has gained popularity, fueled mostly by local residents and businesses. But for the rest of I-81 users (maybe the majority), CG sounds like another barrier - similar to Shamokin Dam - that will divert North-South traffic off of the highway and force it into signaled intersections and delays. That is not a "solution" but a potential headache. Those who have gotten hijacked at Shamokin Dam trying to get to the DMV via Route 15 will know what I'm referring to - a situation so frustrating that that it has required an expensive by-pass fix.
Central Susquehanna Valley Transportation Project - Wikipedia
The only option that avoids the Shamokin Dam problem is a hybrid - a part tunnel/part-grid system that can handle North-South traffic flow but still eliminate some of the ugly viaduct. Please be gentle in responding.