How might we change/regulate internet communication in such a way that someone could anonymously get a message out on the scale of a pamphlet but not on the sca

How might we change/regulate internet communication in such a way that someone could anonymously get a message out on the scale of a pamphlet but not on the scale of a tweet or social media post? Stated another way, my concern is that any changes to free speech might overcorrect and result in it being difficult to anonymously get an unpopular message out to even a modest audience.