That's really quite the generalization. Some forms of jazz are very much like that, yes; however, there are many forms of jazz, particularly focusing on those from 1910-1950, which are very structured in form and don't really lend themselves to being "self-indulgent".
It'd be like me saying that all rock is talentless because it's all just a "fuck the man" wall of distortion. Yes, there's some rock music that's like that, but rock is an expansive genre and claiming that all or even the majority of rock is like that would be very naïve.
I read a book on Duke Ellington in which he expressed concern for the emerging BeBop style's destruction of Jazz. It seems like he foresaw the move from structured, dance-able music to explorative music as isolating the music from the larger population. It's interesting that I didn't understand his opinion until just now. I'm still not sure I agree with it, but I can see how making music less dance-able could turn off people.
Whatever bebop did to "destroy" the jazz that came before it very likely would have happened anyway. The big band jazz of the sort Ellington was best known for was dying out, primarily for financial reasons, and an increasing number of people who wanted to dance along with music were dancing along with rock rather than jazz.
But, looking back at the big picture that even Ellington couldn't see at the time, I don't think that bebop destroyed jazz at all; it was the next evolutionary step, just as Ellington's jazz was a step beyond Dixieland-style jazz.
It'd be like me saying that all rock is talentless because it's all just a "fuck the man" wall of distortion. Yes, there's some rock music that's like that, but rock is an expansive genre and claiming that all or even the majority of rock is like that would be very naïve.