I note an unfortunate confusion between government measures to ban those who may allegedly “radicalise” students on university campuses – which, it is claimed, means encouraging them to support a range of views on Islam, but not revolutionary socialism – and the long-standing practice of no-platforming speakers (mostly unsuccessfully). This latter activity is never directed by the government, but comes from below, organised by opponents of those who are advertised to speak. It has been going on for as long as anything like democracy has existed in the UK, and perhaps a bit before. The government is never involved. For example, after 1945, Oswald Mosley, who believed that the wrong side had won the war, was not only left free to speak but also given police protection to do so. He did not always succeed thanks to the actions of Jewish ex-servicemen, women and others.
Government bans on speakers do indeed smack of official censorship. No-platforming is just the rough and tumble of politics.