I think the media portrayal is a HUGE reason why (1) this condition is so underdiagnosed and (2) why so many people see it as a "joke disorder" in the sense that it's all for "comedic timing".
It took me over a decade to get a diagnosis for why I wanted to sleep ALL. THE. TIME. despite normally getting 6-7 hours of sleep a night. Media portrayal is a huge reason why the idea of being narcoleptic never even crossed my mind. I only began to think I could be it about a year ago and that's when I asked my primary doctor if I could see a sleep doctor to see if it could fit me (and if not, rule it out to figure out what the heck was going on with my body).
I saw another article floating around the internet from a person with narcolepsy that basically described it as "The nap rules me, I am barely keep the nap at bay, all day, because my body is demanding I go to sleep." It's a great way to describe it.