I think you are right, but this means the 230 haters will be super disappointed.

Section 230 is super clear that the social media companies are allowed to censor as much as they want. It's the express purpose of the section to allow "censorship" without incurring liability for those things you fail to censor.

The idea that by recommending or curating content the website owner loses the right to censor that 230 explicitly provides feels like a huge stretch to me.

So the case becomes pretty narrow: Whether the action of YouTube promoting content is protected by 230 or perhaps promoting content is only protected by normal free speech rules including the 1st amendment.