Because i really feel like it can be taken in various ways. A fan that replies to a negative comment regarding the franchise with something along the lines of "You've offended the japanese/american/manga version of the series, i hope you die a painful death and rot in hell" does take it seriously....not in a health way...but takes it seriously none the less. (Yes, that's the extreme lol)
As for me, i take it seriously and i don't.
It "exists" in my life in a big way. I am going on 21 years old, and in the past 16 I grew up with it, moved on to the original version that is now my favorite, moved on to reading the original manga, have wanted to and enjoyed knowing more about the series and franchise, have played games, seen crappy live action adaptations ALL because i do enjoy it so much, because i "take it seriously".
I don't take it seriously in the way of thinking it's the "end all, be all" definitive anime and manga series. I've watched series that i consider better and worse...Dragon Ball just happens to be my favorite






