It was all Lara.
Why do you say he is mentally weak? Do you know how much adversity he has faced his whole life? His childhood was rough, his family and entire village didn't want him to play cricket, he had very few opportunities, he had to fight his way to the top. He is incredibly strong mentally, it's just that when he gest out there, he wants to please the crowd. He is a people person, they are more improtant, because it is just a game. He wants to inspire kids with his big hits, lighten up the crowd, make people want to play cricket. And he does it well.
And as Pak said, if he wants to and if needed, he can apply himself. He is a brilliant player.