The examples she cites - Flat Earth, burning witches etc. are deliberately extreme and ridiculous, but the principle could equally apply to anything. Global warming, Assad's "war crimes", socialism, antisemitism. MH17. The Skripals.
The list is endless. All they have to do is assume a political position, declare the debate over and then silence the dissent for the sake of "public dialogue". This does not make them "anti-free speech":
"No-platformers are not scared - they simply think certain debates are over. You may disagree, but it does not mean they are against free speech."
A beautifully totalitarian position. They will rebrand intolerance as being "enlightened" and "woke" and "progressive".
Don't worry guys - The only debates being shut down are ones which should be, because they're over, according to the Guardian.