From the little that I have learnt (through this very forum, mind!) about the concept of "bokeh", it is - as always and again! - highly subjective as to what is considered a nice bokeh and what is just "blurred background". I have not managed to really get behind the term myself so far, either. My understanding of bokeh now is that it should contain still SOME definition of what is happening in the background, though so little only that it ADDS to the motif in focus but does not distract from it. The motif in focus must still be "in focus" ... also of interest in a photo. But, like I am saying, this is MY interpretation of the term.
This is just to say that the background need NOT always be plain. It CAN also be "living".