Bass is a very easy instrument to get started on. Compared to guitar, there are no chords (which are a usual stumbling block), and getting a serviceable bass tone is about as easy as plugging in an instrument - unlike a lot of string, brass or woodwind instruments that take many hours to achieve quality tone and playing technique.
Bass is the Othello (you know, the game) of instruments - easy to pick up but it takes a lifetime to master.
The subtleties of the bass are the beauty of it; they take a long time to nail down. When you hear someone who's truly mastered a bass, you can tell...
...but let's not let our own pride fool ourselves - bass is a pretty easy instrument to start on! It's also normally not in the center of attention, whether we want to think it is or not.
PS - The book would be biased
against bassists if it were talking down about them.
