Making an argument for 'misinformation cesspit' over 'moderation' is just never going to be an argument you can win. Not with the business, and not with the public. This is one of those 'perfect is the enemy of good' things. If you don't give them a good business option to take, you will get handed the easy one (and it sure as shit is not going to be perfect).
While presenting misinformation is a political act, it is a more 'neutral' political act. In that, since many people are able to put forward content, that doesn't stop ideas from either side. Yes, that doesn't mean that truth will automatically come from that mix, but it allows for the potential of truth to be found. When you have a massive company controlling so much of content, it has a large amount of ability to influence the people using the platform. As well, I think banning misinformation is a legitimate slippery slope. It increases people's willingness to have other's censored for their incorrect beliefs, which once you have gotten far enough will be the new normal.
Just like drug addiction, each step along the path to censorship is a clear decisive act. I am way more concerned about the fast train to banning encryption than the baby step of banning misinformation.
And by the way, let's also not lose sight of the fact that presenting misinformation is a bastard political act itself. Fuck those people.
Edit: *on a non government platform