Traditional "street" photography involves some "in your face" interaction with your subjects, so a normal to moderately wide lens is usually used... maybe a short telephoto in some instances. Arguably, "street" photography is NOT standing off in the distance and "sniping" candid shots with a moderate to long telephoto lens. And too wide a lens would risk too much perspective distortion. So on 35mm film rangefinders 28mm, 35mm, 40mm and 50mm were popular, while 70mm to 90mmm were possible. On an APS-C digital today 18mm, 22mm, 23mm, 30mm or 33mm would be top choices.... with 50mm to 60mm possible.
My own compact APS-C kit, partly for street photography, includes four lenses:
12mm (not so much for street, more for scenic shots)
22mm (equivalent to 35mm full frame)
56mm (equivalent to 90mm on full frame)
90mm (not much use for street, a macro lens)
I'm just not a fan of "normal" lenses, so don't have a 30mm to 33mm lens in my kit. This is just my own preference. Many other folks enjoy their "normals" and take lots of great pics with them. I may add a 33mm some day if I get a good deal on one, just to have it in the bag, if needed. I've also looked at a 16mm (approx. 24mm FF equiv.) because there's 18mm available for my particular camera system.
A compact camera that doesn't attract attention is preferred by many street photographers. This is so they can get in close without alerting their subjects and is another reason for lenses in the 22mm to 33mm range, which can be fairly compact and unobtrusive. Some of the non-interchangeable lens digital cameras can work well for this, too. I'd look for the largest sensor possible (APS-C or micro 4/3 or at least 1") in combination with a zoom that has approx. 24mm to 70mm or 24mm to 90mm full frame equiv. range.
These were done with 28mm lens on APS-C:
As you can see, on this group "walkabout" I found the other photographers among the more interesting subjects!