That seemed to be what Zuckerberg was saying in an interview with the Washington Post. Zuckerberg responding to complaints that Facebook was allowing people to lie in political ads:

"'People worry, and I worry deeply, too, about an erosion of truth,' Zuckerberg told The Washington Post ahead of a speech Thursday at Georgetown University. 'At the same time, I don’t think people want to live in a world where you can only say things that tech companies decide are 100 percent true. And I think that those tensions are something we have to live with.'"

Zuckerberg apparently feels tech companies lack the competence to determine the truth of claims that people make in ads and elsewhere. Traditional publishers make this determination all the time. They refuse ads that they believe to be false and issue corrections for ads that they run and then later are presented with proof that the ads are false.

It may well be the case that Facebook is run by incompetents, but that is an argument for improving the quality of its staffing, not allowing it to be a medium for spreading lies.