Extremely talented. It's just that the white calligrapher is not as good as the king since ancient times.

Very talented, only white.

Calligraphers are inferior to kings since ancient times.

It means: Bai (personally, maybe not) is very talented in calligraphy, but all calligraphers are not as good as Wang Xizhi (he is a book saint).

I don't know if it's right. Please forgive me if it is misleading.