Picard isn’t afraid of dealing with more advanced cultures.
Maybe it was because they were just figuring out the universe. Or maybe it has some deeper meaning but whatever it is, Kirk isn’t the greatest at dealing with more advanced cultures. Not to say he doesn’t try, he’s just not that good at it. But Picard is.
It probably has to do with the fact that, again, Picard is a diplomat. He is someone who focuses his time and energy on trying to make the universe run as efficiently and peacefully as possible. So he isn’t afraid to deal with cultures that are highly advanced. Some are even more intelligent and progressive than he is but he isn’t afraid to face them head on and talk through things.
That is the man point of this, I think. Picard is a talker. He will discuss things and figure out the best course of action. Kirk sees something he doesn’t understand and he acts before talking it out. And in some situations, that makes it worse for everyone involved.
So Picard is better in this sense because he will talk to the other cultures he does not know much about. He will learn and react accordingly. Kirk just does what he thinks is right without thinking about the consequences.