I've been following Argentina's struggles for a while given my time in Brazil and the parallels to hyperinflation so I was willing to consider his unorthodox approach, but perhaps it blinded me?
Reasons for liking him: he's bringing inflation down, he has been keeping his promises towards retirees, and he's been reigning in some egregious examples of corruption that previous administrations ignored because it gave them political power.
Reasons for not liking him: he's strangling Universities, rent prices are out of control and not properly reflected in the inflation index, and after being first row during Trump's inauguration he decided to withdraw Argentina from the WHO.
A friend of mine who doesn't like him described his policies as "Ron Swanson from Parks & Rec". I think there's a lot to it.
Whether or not Milei truly wishes to help his country, or if he's using his power for personal gain, is difficult to say. As an outsider, I don't have an informed opinion. But I'm inclined to believe that the truth is somewhere in the middle. The reality is that the vast majority of people who seek political power are egomaniacs and sociopaths. Very few actually want to help their country.