It is true that scarlet blaze have the +50% boost from the talent, but you seem to forget that azure fang have the elemental strenght boost against wb, because the world boss is fire elemental. And if we do a comparison between what af and sb could do singlehanded against the wb we see there's no match. Azure fang have the strongest single target mystery there is among the mains, skewering, and have both an high crit standard attack, a full nin damage high combo chase and a clone with a nin/tai standard attack while sb have no high damage single target mystery nor any high damage standard attack against an immune target and his high combo chase is more or less comparable to af one (and no clone if you use the 50% boost). The reason why was added that talent for sb in 2.0 was because sb was so behind the other mains that needed an enormous boost to try to be on par but singlehanded is still way behind azure fang against it. The reason why sb right now has the upper hand is because can boost other ninja better suited for wb than af (that only boosts gnw tenten among the viable ninjas for wb).