No, Ness hasthe strongest spike in terms of hitstun (which is all you really need for a spike).
Ganon's spike has more knockback and killing power bascially. If you are in the water, Gnon's spike will kill a few points earlier, and it will kill much earlier than Ness' on a grounded opponent, BUT, hitstun is what you want in ta spike.
Ganon's spike sends opponents 5 stage builder squares down before the hitstun wears off. Ness' sends them down 7 squares.
Even if people consider Ganon's stronger, Ness' has a humongous disjointed hitbox under him (think Snake's utilt downwards) that FAR surpasses Ganon's.
Ness spike>All