Street confrontations are something that you should evade by all means. However, when the push does come to shove, you want to be prepared. Which is one of the reasons why Jiu-Jitsu is so great.
However, not all confrontations are made equal. John Danaher elaborates:

Please understand that not all confrontations are of equal intensity. There are massive differences in terms of scale and level of intensity, in various kinds of confrontations.
Things can go from a minor argument in a supermarket, all the way up to situations where people are fighting and dying on the street, with weapons involved.

With that said, one of the most amazing things about BJJ is that you can adjust how you’ll respond to the varying degrees of confrontation intensity:

One of the true beauties of Jiu-Jitsu is that it offers you tremendous variations in the intensity of your response; which you can then apply appropriately to the intensity of the situation you’re in.
So often, I’m kind of amused by self-defense instructions where you see people advocating: “Just go straight to eye gouges”, to fish-hooking people… I mean, there’s certainly a place for these techniques. But there’s also a lot of times where you’ll want to use self-defense responses; where those would be completely inappropriate.

Professor Danaher goes on to explain that Brazilian Jiu-Jitsu enables you to go from a mild to a potentially deadly response:

We live in a litigious civil society. Our responses to the aggression we’re trying to confront must be appropriate to the situation we find ourselves in. One of the chief advantages I find with Jiu-Jitsu is that you can easily do this.

Jiu-Jitsu offers very mild weapons of control; where you can take someone down and control them in the most mild fashion. And that ability to run the full scale of the very mild response to a potentially deadly response is one of (Jiu-Jitsu’s) chief advantages.