Man I know some "sport bjj" brown and black belt guard players, berimiboloers, xguarders, spider guarders, that would completely destroy your regular 7/11 thug variety in a street fight.
However I only say that because they have been playing these positions for years and are just way to strong and slick to let some bum stand over them and beat on them. They'll be swept, reversed or leg locked in a matter of seconds.
Set the clock back to when these guys were blue and even purple belt level and I can say these positions are dangerous as fuck to try to pull off in a street situation especially if your opponent has even an ounce of gameness.
Laying on your back spending precious time trying to set up a deep half sweep or trying to recover your spider guard could get your head bashed in.
A less skilled bjj fighter will be far better off in a street situation by adhearing to the classic bjj fundamentals: close the distance, enter the clinch, take them to the ground, pass the guard, obtain a dominant position, submit.
I'm all about the evolution of bjj and for the most part I'm excited about learning all this new wave stuff, but at the end of the day all the guards and new age leg entanglements are defensive positions, positions that you use if your opponent puts you on your back, a place that a competent fighter should only be in if all other offensive and defensive measures have been exhausted.