soloing skills aren't the thing that people are prizing.
I don't think anybody is saying bass players are getting hired only because of their soloing skills. It's this dumb old argument that people say "Play in the pocket and you'll get hired, nobody wants to hire a soloist." Obviously if you suck at actually playing the bass nobody will hire you regardless of your solo chops. But that's not the point here, the point is that if you are a good bassist, and can also solo well, you get more gigs, not less.