The FCC isn't a court, and it certainly isn't an appeal court, but it could certainly decide how § 230 applies to its own regulatory actions, which are subject to the law. A doctrine called Chevron deference, based on the case of the same name, means that courts, when addressing such legal interpretations by agencies with responsibility for enacting such laws, generally defer to the administrative agency.
However, the FCC has no real authority to decide what happens when private parties sue each other. That is entirely court-created doctrine that the FCC has nothing to do with. They are very unlikely to defer to the FCC's general opinion about something that doesn't concern them. Especially from a smarmy street shitting piece of garbage like Ajit Pai.
Not really. Only in the context of FCC regulatory actions, and even there, rulemaking is subject to public comment and other processes, and formalities have to be adhered to. As much as I detest that motherfucker, I don't think FCC regulatory actions are a huge threat to the Farms specifically. What we have to worry about is private civil liability. The government does not give a single fuck about us.