Jujitsu like any fighting disclipine is applicable in a street fight, the system is not at question but how you apply it and who you are fighting is.
For example if you freez nothing will work until after you wake up and prepare for the next time. If you purposely pull guard on a good wrestler or a person good at ground & pound you may have done the wrong thing. If you are intent on grabbing miss and catch a right hand that drops you, you may be in deep trouble. All in all Jujitsu techniques are just as competent as any fighting disclipine it how you apply them that is the X factor. Its not what you train in it how hard you train it. You make your Art it does not make you. JJ covers most ranges.
Also, In my view traditional jujitsu mixed with techniques for self defense on the streets will be a lot more effective.