Calligraphy is written on paper and boards, generally according to the needs of the environment. Writing and collecting have different values. Such as building plaques, colonnades, screens made of precious wood, furniture, etc. The words of famous calligraphers are carved on the board, which has high appreciation value and collection value. Calligraphy written on paper, after mounting, has different artistic effects from calligraphy written on wooden boards. Because the age and calligrapher's situation are very different, they generally don't compare value.
It is not as easy to store, hang and collect on wooden boards as it is on rice paper and silk.
Attached are pictures written by Pan Shouyu, a famous scholar and calligrapher, on rice paper and wooden boards. See the effect.