If only you were capable of actual answers, or of even backing up your claims
It can apply but only in very specific circumstances (i.e. if the person sues the site for the speech hosted on the site, the First applies, since the First applies to the Courts too, or the Trump's twitter situation where courts ruled that Trump's personal Twitter account was subject to first amendment and that by blocking people, he violated the First (
EDIT AS OF April 5th. The Trump decision was overruled by the Supreme Court). But, you are right, if you get banned of a site, or your thread is deleted, First doesn't apply.