Congress and the broader US government is going to be making a dedicated effort to ensuring the American public is kept in the dark as to their illicit activities. Trump and the Republicans are steering the country towards authoritarian fascism and want to keep information stifled, so it should be made mandatory at all times.
Yes, congressmen should be allowed to go live on Facebook from the House floor. One of the greatest problems with our government is not that there is too much transparency, it is that there is too little. Going live from Facebook would provide citizens with an invaluable way to keep track of the activities of their representatives.
Congress must not ban broadcasting from the floor. To do so would allow those in power to shut down presentation of any ideas that they do not agree with, which goes against democratic principles. Congress represents the people, so the people should have access to what is going on in the halls of Congress. Facebook streaming provides an important means through which this can occur when those in power try to shut down the public's access.
It took a long time for Congress to accept CSPAN. However, it did recognize the changing times and allowed CSPAN. Just like CSPAN, allowing a Congressmen or Senators to go live on Facebook should be recognized as an acknowledgment of changing times. It is an even more immediate way for members of Congress to reach their constituents.