Likewise, if people perceive themselves as significantly endangered by some forms of communication, they have an interest in disrupting it. One could counter that they should argue an alternative point of view, but this presupposes that all arguments are made and evaluated in good faith, and that all disputation is substantive in nature, without any use of rhetorical figures or exploitation of cognitive biases. As we know to our cost, this is often not the case.
It's equally possible that people might want a channel for anonymous complaints because they don't feel comfortable or safe articulating their unhappiness over an issue in public - that is, they feel their own speech to be chilled, directly or indirectly.
Your argument seems to rely on the assumption that that can't be the case, based on events that have happened subsequently - as if the news from today about Paypal is necessarily a consequence of the Cambridge (not Stanford) litigation, when it might be in response to something else entirely; the substack author didn't bother to mention any recent controversies, perhaps assuming that her audience were already following the group's fortunes closely.
The purpose of the portal was to snitch on white people for wrong think and it was taken down for a legal reason.
False equivalency. Setting up a snitch website has little to do with speech and everything to do with administrative action.
Clearly, many people here don't understand jack about why free speech is important. They just parrot that phrase when they feel it advances their pet ideology, literally not understanding what it means. They treat it as if it's just some clever construct made up by "the other side". This is how we get persistent false equivalency between communication and disrupting communication.