The first amendment is to protect people from (the government/Congress) exercising their speech in public arenas, i.e. Government owned arenas. If speech were protected everywhere at anytime, trespassing on private property(including businesses) could not be a law created and enforced.
The argument to protect speech in private arenas falls deaf on me because no one is saying that people can not create their own platforms to share their vision/speech and create their own communities. That takes hard work, a good message/product and time.
The argument, broken down, says that any idea by 1 person, no matter how maliciously intended, can exploit the work of companies like FB, twitter, youtube and access their user base EVEN WHEN those companies want to have 0 association with that person.
It is the equivalent of dressed KKK members attending a Bulls game and saying the Bulls have to let them remain all throughout the stands for the entire game, no matter what they are chanting.
'Amendment I
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.'