Praise be to Allah.
Undoubtedly this kind of cursing is haram (impermissible). Even if we say that the pen and paper have no religion in the sense of doing acts of worship, nevertheless the religion is one, and it is Allah Who has subjugated these pens and other tools and made it easy for us to use them, so there is the fear that this cursing may be referred back to Allah. So this person has to repent and seek forgiveness, and not do anything like this again.
And Allah knows best.