a couple of options, here. either Ben Solo was a lil nerd who VOLUNTARILY noted down Jedi texts by hand (in a culture where hardly anyone writes!!), OR Luke encouraged him to do calligraphy as a (failed, lol) anger management technique.
remember when in young avengers kate was shook bc her whole team was gay except her, and then america shut her down immediately, thus confirming that there’s not a single straight young avenger?? iconic