No. I would say the North lost more traditional culture compared to the South, considering it was under a communist regime for decades longer.
Similar to the Cultural Revolution in China, though not nearly as bad, many elements of traditional culture were not looked at kindly by the communists.
It’s kind of like China and Taiwan, in that China has lost more of its traditional culture compared to Taiwan. Or North Korea and South Korea.
Just because Southerners are more cosmopolitan, doesn’t mean they are less traditional than Northerners.