Thanks for bringing that point up Jim. I looked at this one again a little more closely, usually exaggerated profiles are because of sharpening.
However this one, having looked again just now is not. Obviously designed that way.
But I have a theory.
The use of large hide shields is well established in Sahel warfare. These were typically carried by Tuaregs and also saw use in Hausa areas, although from what I have seen in very early period photos it was perhaps more a Tuareg defense than widespread among Hausa cavalry. The Tuareg by most accounts engaged in a style of swordsman ship which was primarily made up of cuts and slashes focused towards the last third of the blade (clearly evident by blunt tips and sharpening focused on the last third of the blades). They rarely wore heavier body armor from what I can tell.
However in Hausa land the cavalry adopted thick, quilted armor known as Lifidi, which was apparently very effective against arrows and probably also slashing cuts, due to the multiple layers used.
It would make perfect sense then to see a Hausa takouba adopt a piercing tip for thrusting as can be seen on arm daggers from the area. An interesting note is that the quilted armor lead to an upswing in the use of fire arrows which led to water being carried onto the battlefield expressly to douse the knights!