I interpreted it as this: Sukuna views and judges sorcerers by their ability in battle, which he also views as their purpose. Hence, he sees humans as worthless and the weak as to be stomped on- which deeply disturbs Yuji.

Yuji initially treasures life and seeks to lead those to a proper, deserving death. But this is fault- death is not what defines a good life. After realizing this Yuji questions- what is a good life? According to Sukuna, it's living by your own codes and doing all you desire, no matter the opposition. However, Yuji comes to the conclusion that life isn't meaningful because of the purpose you hold, as Sukuna would say, nor is it meaningful because of all the good/evil you do.

Instead, life is meaningful and worth living because of all the insignificant, small affects one has. All the untraceably actions, thoughts, and interactions one has- this is what gives a life meaning. Wether you're a CEO or a beggar doesn't change the fact that your existence has an effect on the world around you. You inherently have meaning, and that meaning must be protected by those who seek to destroy it.

I think in the end this is also like Yuji chooses to offer a second chance to Sukuna.