At least in case of Section 230, distributirs that do not moderate do not need it because they do indeed have that kind of legal protection - see Cubby v. CompuServe for an example. Section 230 was created because a provider that did moderate tried to use this precedent in court and its applicability was rejected, and Congress decided that this state of affairs incentivized the wrong kind of behavior.

This is precisely why Republicans want to repeal it - if they succeed, it would effectively force Facebook etc to allow any content.