Nah Luffy wasn't presented as special beyond having Inherited Roger's will all the way up until his encounter with Aokiji where we hear his grandpa is a big deal. And then his grandpa is revealed, and his dad too (all big shots).
And then Fishman Island comes and boom Joyboy connection. And then Wano the Nika fruit.
You are making it sound worse than it is.
Luffy's dad who is a big deal abandoned him and never influenced any of his decisions.
Luffy's grandpa is a marine and he influenced Luffy to join the marines, he even tried to convince him to never become a pirate.
However, Luffy met Shanks one day and he got the will to become a pirate and be the pirate king.
Luffy inherited Roger's will at becoming the pirate king.
However, for Luffy, the pirate king is the one who is the "freest", he only wants to have an adventure and travel the world.
Given that his dream is about freedom, the Nika (rubber) fruit decided to be eaten by him since fruits have a will of their own.
In his quest at becoming the pirate king and at becoming the freest, Luffy frees people and nations from oppression, like the warrior of liberation Nika, like the previous person who awakened the Nika fruit 800 years ago (JoyBoy).
However, Luffy doesn't give a fuck about that and he doesn't want to be a hero, Luffy wants to become the pirate king.
Isn't it beautiful that while Luffy simply wants to become the freest, eat as much as he wants and become the pirate king, he frees nations from oppression and he is freeing slaves from the oppression of the world government?
Luffy will never fight the World Government directly, there won't be such a thing as a "war against the world government".
Everything that Luffy will do will be in his quest at becoming the pirate king, protecting his friends or his "dream".