What historical facts can Yuanhui’s epitaph confirm?

Emperor Xiaowen reformed and unified speaking Chinese. The historical facts that can be confirmed by Yuanhui's epitaph are that the epitaph is written in Chinese, which can prove that Emperor Xiaowen reformed and unified the Chinese language, and Yuanhui's name can prove that Emperor Xiaowen changed the Xianbei surname to a Han surname, which can prove that Emperor Xiaowen learned Han culture. "Yuan Hui's Epitaph" is one of the representative works of calligraphy in the Northern Wei Dynasty.