A wrestler with the improved Sunder feat who manages a Greataxe is performing a sund attack on an opponent who wields a longbow.
PHB p113 indicates that a long arc is a projectile weapon and that most projectile weapons require two hands. Then, the PHB further explains on p314 that a two-handed weapon is "a weapon designed to be used in two hands".
Sunder's description indicates that the holder of a two-handed weapon has a bonus of +4 in the attempt to sund.
In that case, would the defending player resisting the fall of the greataxe benefit from a +4 bonus on his opposing attack roll?