Why didn't calligraphy in the Northern Dynasties get attention for a long time?

with the establishment of the Northern Wei Dynasty and the reform of Emperor Xiaowen, the severely damaged northern economy began to recover and develop, followed by cultural prosperity. In this context, the calligraphy art of the Northern Wei Dynasty has been greatly developed. During this period, the style of North-South tablet calligraphy has gradually reached a comprehensive trend of unity.

..... The calligraphy style of the Northern Dynasty was inherited from the Han stele, which was simple and unpretentious, conservative, rarely flexible, and clumsy, unlike the romance of the Southern people, so it was different from the calligraphy style of the Southern Dynasty. (the main reason) ......

Moreover, many people erected monuments in the Northern Dynasties at that time, unlike the Southern Dynasties, which prohibited the erection of monuments. The Cui Lu clan in the Northern Dynasties was good at writing and famous works, and naturally built many monuments. In addition, Buddhism prevails in the north, and there are few inscriptions on statues. Many of them were made by masons, especially statues. Therefore, there are many wretched and vile people, but there are also many good ones. At the same time, since the Tang dynasty, the handwriting of the two kings has been emphasized, and Song inherited his style. Therefore, few people care about the stele in the Central Plains and let it be eroded.

However, there is also an advantage, that is, there are few developers, so the monuments erected in the northwest provinces thousands of years ago often still exist today.