Colin Wilson had a meteoric rise to fame in 1956 when his first book 'The Outsider' was published - but within months he was being vilified and shunned by the British Establishment; and his reputation has never yet recovered among their descendants.
The usual reason given is 'the horsewhipping incident' which was splashed all over the newspapers - in which Wilson's cohabiting girlfriend's father arrived at his door to threaten him with a horsewhip as punishment for various sexual acts (some real - e.g Wilson was married to someone else at the time; some imaginary and based on having read a fictional diary as if it was factual).
Supposedly, after this salacious incident, Wilson became a mere 'tabloid' character ('famous for being famous') and nobody could ever again take Wilson seriously.
But I don't believe this is true. Sexual misdemeanours and embarrassing, even humiliating, sex-related media scandals were quite normal - indeed more usual than not - for radical Left-wing intellectuals throughout the whole twentieth century; and particularly in from the mid fifties and into the later sixties. The horsewhip incident would normally have enhanced Wilson's reputation --- If he had been a Leftist...
The real 'problem' for Colin Wilson is that he was regarded as a fascist - and that was, and is, unforgivable. It was, and is, enough to exclude him from approval by the Establishment forever.
It must be recognised that Wilson's fascism was as that word is defined by the communist-sympathising Left of his era. In other words Wilson's fascism was because he was known to be anti-Communist. At the time Wilson was mildly Leftist in politics; but that did not, and does not, matter - fascism was and is defined by the Left as being against whatever happens to be the dominant Leftist ideology of the era, and in the fifties that was Soviet Communism.
On top of that Wilson was known to be focused on religious and spiritual matters - rather than socio-economic equality - and this was (and still is) regarded as fascist (despite that fascism was a secular, typically anti-Christian, ideology). But the Left was correct that most thoughtful and coherent religious people are anti-Communist, and anti running society on primarily Leftist lines; and that was (and remains) enough to make them a fascist.
On top of this, Wilson was a close friend of Bill Hopkins, who really was a kind-of fascist!
Other, later, friends included Brocard Sewell and Henry 'Tarka the Otter' Williamson who were friends and supporters of Oswald Mosley - the would-be British Nazi dictator of the 1930s. So Wilson's circle in 1956 and later did contain 'real' fascists - Wilson did not shun and vilify them, as the Establishment require/d.
At any rate, the emerging Angry Young Men literary group, of which Wilson was one of the originals; was soon divided (and divided itself) into Left and not-Left/ religious sides - and Wilson found himself on the shunned side of that divide; as did Bill Hopkins and Stuart Holroyd, whose careers were also permanently blighted.
I am not claiming that the horsewhip incident and the sexual scandal was utterly irrelevant to Wilson being regarded for the next sixty years as either a pariah or a joke; but that 1. it was insufficient to account for Wilson's lifetime of shunning and 2. that the scapegoating sanctions would not have been applied to Wilson if he had been an adherent of the mainstream, pro-communist establishment.
So, in a sense, Colin Wilson was the first prominent person to be a victim of what would later be called a political correctness witch-hunt; and which is so regular a feature of modern public life.
Biographical reference: Beyond the Robot: the life and work of Colin Wilson, by Gary Lachman, 2016.