Answer:
He meant that he doesn't know anything about politics because he doesn't want to try to understand about it, preferring to keep non-knowledge and, therefore, rational ignorance.
Explanation:
Rational ignorance is the term that refers to the human being's ability to keep believing in a wrong or insufficient concept, as he does not want to bear the search for information and the costs to better inform himself about this concept and understand it efficiently, that is, to an individual in a rational way and by his own choice, he prefers to remain ignorant about a certain subject.
In this case, when someone says that he does not know anything about politics because of rational ignorance, it means that he knows that his knowledge of politics is insufficient, but he or she prefers to continue like this, because he does not want to be informed about politics.
