1) the Electronic Frontier Foundation (EFF)/Techdirt liberal/libertarian view that Twitter, Facebook, etc. are private firms and can do what they want and
2) the Trump/Hawley/social conservative view that social media platforms should lose section 230 immunity and be regulated as public utilities with mandatory viewpoint neutrality.
Position 1 is also supported by empirical claims that without section 230 protection the internet as we know it would never have developed (see The Twenty-Six Words That Created the Internet).
My propertarian libertarian view is close to position 1 but with caveats. Social media platforms are indeed private firms and can publish or edit (they cannot censor, a term that refers exclusively to state actors) whatever they like—subject of course to the terms of service between the platform and users who generate content. However, I think section 230 is bad policy on procedural or rule-utilitarian grounds. Congress should not give particular firms blanket immunity from common-law civil causes of action via statute. Rather, these issues should be handled by contract law as enforced by courts, not by legislation.