I’m responding to your comment more as a representative of a general sentiment.
The implicit psychological construct behind this little “mini-panic” around fringe groups be “de-platformed” is a common one: something bad is happening, and we are losing freedoms/rights/capabilities we (society) has in the past.
It’s a variation on the notion that “the world is going to hell a hand basket.” The rhetorical fallacy is called “false idealization of the past.”
In fact, the access of everyday people to a variety of mediated forms of communication is at historically unprecedented levels.
In virtually the entire history of human society, access to powerful methods of communication was completely under the control of the elite power structures of the society.
The problem that these new communication platforms are trying to deal with is unprecedented. It turns out there are unexpected consequences of allowing access to mass communication, and means of spreading propaganda, to “fringe” groups like “white supremecists” The problem is unique in a couple of ways.
One is that it is only very recently, very recently, in our society (the US in this case) that the precepts of white supremacy have been “fringe!” In fact these are the hateful ideologies that built much of our modern world, on the backs of those unfortunate to have not been born “white.”
This has been hard fought-for progress, and banishment to the “fringe” of these ideas is a major success. The attempts to drive these ideas even further to the fringe represents a triumph of humanistic values. Especially as reactionary groups inevitably fight back with whatever means they have at hand.
It just happens to have happened right around the time that technology put methods of mass media into the hands of more and more everyday people.
Using “De-Platforming” as a method of social control is entirely civilized, and justified. We have bedrock principles of free speech in the US, but those are almost entirely based around the idea of preventing the government from jailing speakers it diagrees with.
To raise an alarm about, “well, what if your currently considered ‘progressive’ movement is deemed deserving of De-Platforming in the future” is a false alarm, because there simply are no historical examples to draw from. These technologies are too new. (Not just the technology, also the increasing ubiquitousness of networked communication.)
It also pretends that in some philosophical sense, all ideas are equally valid, and is divorcing the content of ideas from the form.
I don’t agree that all points of view are equally valid, and viewing ideas through the lens of “form” over “content” is antithetical to the very core concept of ideas and thought itself.
IMO, people are too quick to trot out “slippery slope” fears about difficult problems. However, we can’t get “off of the slope” in a metaphysical sense. We are alive, until we aren’t,and must navigate the treacherous slopes of reality to the best of our capabilities. As both individuals and as members of society.