I have three humble opinions.
First of all, hard pen calligraphy is widely used in our life. Except for a small pen, it can basically solve our daily writing communication without other auxiliary equipment.
Secondly, the connotation of Chinese characters must be written out to be reflected, and sometimes it is equivalent to the connotation of people.
When you want to know a person, you'd better observe his handwriting first. If his handwriting is neat and beautiful, even if you have never seen his real person, you will definitely think that this person has extraordinary temperament and good cultivation. But if a person's handwriting is scrawled and deformed, then you will definitely think that this person is impetuous and has no talent.
Thirdly, I think hard pen calligraphy is a very profound art, which is ignored by most people because of its simplicity. After all, people nowadays are so eager for quick success and instant benefit that it is almost impossible to spend time studying whether their fonts are ugly or beautiful. This also tells us in disguise that mastering beautiful hard pen calligraphy can better reflect the value of being a China person than mastering thousands of words.