Life and death balance on the edge of Genji's blade. However, the number of swings Genji can get with a newly discovered animation cancel is not quite as balanced.
Reddit user K_Cujo
When Dragonblade is active, climbing a wall resets the cooldown of Genji's attack, allowing him to immediately swing again. Even though he reset is very situational (an enemy has to be backed up against a wall), it does add utility to Genji's already flexible kit.
It is very likely that the animation cancel is not intentional, and could be patched out at some point, similar to Genji's edge dash.