This pen appeals to those who like functionality or view themselves as people with discerning preferences. The design is simple: beige and black says minimal in a functional way.
Right next to the logo, in biggest font size and different font style and color is the width of the pen tip. This is the most essential information and it is presented as such, showing consideration for the user’s needs. This detail is also arguably why the pen is so desirable. The design draws people who care about penmanship, perhaps those who want to be taken seriously as someone who knows about line weights and technical drawings even if they only use the pen to take notes in class. It carries the seriousness of a professional drafter or designer. It is also salable to corporate firms and classrooms for manual drafting because the product performs well and has a neutral, frill-less design.
Maybe the user is led to believe that the pen serves its function better than it actually does due to these visual cues. I certainly get annoyed that the felt tip can easily go from a 005 to a 01 if one accidentally applies too much pressure; a Pilot steel-tipped pen would work better in that respect. Generally the product delivers though, so it seems desirable with good reason.