To take it a little farther with actual numbers, here is what some other teams have held UNC to this year:
VT--172 yards and 11 first downs
UVA--257 yards and 12 first downs
Notre Dame--265 yards and 13 first downs
GT--247 yards and 11 first downs
Duke--377 and 15 first downs
Then, against us, they went for 428 yards and a whopping 27 first downs. That's pretty awful when viewed in the context of what they've done against their other opponents. That's a ton of resets to 1st down when you give up 27 first downs.
I genuinely do appreciate you decided to play contrarian on this one, because it made me look up more context and further supported my point. Here is the answer to your stats above. I'll repeat I'm not saying the defense is elite. I'm saying the defense isn't bad and also that your points, so far, aren't supported:
You said: VT--172 yards and 11 first downs
VT offense produced 181 rushing yards, 21 first downs, 4 total non-TD drives of 4 plays or less
You said: UVA--257 yards and 12 first downs
UVA offense produced 151 rushing yards, 23 first downs, 4 total non-TD drives of 4 plays or less
You said: Notre Dame--265 yards and 13 first downs
ND offense produced 341 rushing yards, 27 first downs, 4 total non-TD drives of 4 plays or less (2 caused by Turnover), their offense basically crushed UNC with control
You said: GT--247 yards and 11 first downs
GT offense produced 403 rushing yards, 22 first downs, 4 total non-TD drives of 4 plays or less (1 caused by Turnover), their offense basically crushed UNC with control
You said: Duke--377 and 15 first downs
Duke offense produced 186 rushing yards, 20 first downs, 3 total non-TD drives of 4 plays or less
I have no agenda other than to try to find out the "why" through some objective measures - whether watching the plays or the data.
My position is the defense has failed to meet fairly lofty expectations, but are performing decently well according to the numbers comparable to opponents within proper context. If you want to attack that position, we can continue to look stuff up.