Why study chords on the electric bass? In my opinion, there are several reasons, agreeable or not, that have driven me over the years, to take this path, on an instrument that, indeed, is not "properly designed" to perform chords. Among the main reasons, first of all, I believe that the more or less in-depth knowledge of the main chords, opens, even to us bassists, a new world for improvising, or for creating melodies, or even arrangements for solo bass. It also "forces" us to have an even deeper knowledge of the bass fretboard (a topic that I think is fundamental) since it will be necessary to know all the notes of any chord, no longer limited to the Root. We can also use chords only on certain occasions (this depends very much on the context, one's taste, playing style, etc.), for example as embellishments, or (as I very often do) on the endings of songs. The study of chords is also vital for those interested in studying or deepening the Walking Bass (I have written a book on this subject, available at this link - https://www.igorsardi.com/walking-bass-course).
To summarize, a good knowledge of chords, is in my opinion, a great step forward in our study path, even for us bass players. 
I would like to preface this by saying that this is not a didactic book; rather, I would call it a kind of (step-by-step) concentrated course on the subject. I am not going to repeat, for example, the difference between a inversion and a voicing, or what are harmonic substitutions, harmonizations etc, as you can find all these topics in great depth, in my books, especially in my Applied Harmony course - https://www.igorsardi.com/corso-armonia-applicata-per-bassisti 
And in the first volume of “Jaco Pastorius: Complete Study” - https://www.igorsardi.com/jaco-pastorius