Does the Dual Wielder feat require me to have the Two-Weapon Fighting fighting style as a prerequisite?

Say I choose the fighter class, and pick Two-Weapon Fighting as my fighting style; later in the game, I choose the Dual Wielder feat.

Does the Two-Weapon Fighting fighting style become obsolete, if Dual Wielder’s benefits are superior to the Two-Weapon Fighting fighting style?

And is the Two-Weapon Fighting fighting style a requirement for Dual Wielder?