Putting the fictional Sopranos aside, as well as the Outfit, which had a unique hierarchical structure at one time, what real life examples are there of a Street Boss and an Acting Boss being different? Or there being a "head captain" in a family who was the Street Boss?

Obviously the official Boss of the Colombos is Carmine Persico. But since he's in prison for life, he's not in a position to run things day-to-day. So there's obviously going to be somebody who's Acting or Street Boss position precisely because they are on the street an in a position to run the family directly. And this certainly isn't unique to the Colombos.