Section 230 of the Communications Decency Act protects Facebook for publishing content provided by users. 43% of U.S. adults get news from Facebook. Other news sources like newspapers, TV, and radio are regulated, so why not Facebook?
A number of attempts have been made to limit Section 230 protections, for instance:
In June 2019, Hawley introduced the Ending Support for Internet Censorship Act (S. 1914), that would remove section 230 protections from companies whose services have more than 30 million active monthly users in the U.S. and more than 300 million worldwide, or have over $500 million in annual global revenue, unless they receive a certification from the majority of the Federal Trade Commission that they do not moderate against any political viewpoint, and have not done so in the past 2 years.
Rather than regulation based solely on the size of the company, or creating a government department for determining political bias, a better form of regulation might be to selectively remove section 230 protections from companies based on audience reach of individual posts.
Social media companies have proven capable of tracking views so they can bill advertisers. Thus legislation removing section 230 protections from any post or advertisement receiving over, say, 1,000 or 10,000, views would be easy for them implement. This would require the company fact check such trending posts, and put the company on the same footing as newspapers which are liable for the information they publish. There is a big difference between a message sent to a few friends and a story that gets widely disseminated.