its sensible becuase those controllers suck, you cant change sensitivity when the controller you are using has less values than the original wich is the case.
basicaly any CC or hori pad the analog has a limit of values of 1 to 128 and the c stick has even less if im not mistaken it was around 1-63 or something really low.
while the GC controller sticks had values of 1-256 so yeah you can see why CC and fightpads and whatever look very sensible in nintendont becuse they have hardware that is very crappy and limited so anytime you tilt just a bit on the c stick is like you tilted 4 or 5 times on the gc controller, nintendont needs to extrapolate the 1.63 into 1-256 so you cant never get the same sensitivity and theres nothing that can be done since your CC/fightpad/ccpro does not have the same or more values than the gc controller, the wiiu pro on the other hand has more values on each stick so you even get a smoother sensitivity than actual gc controller lol.