He is very much sane and has had the intelligence to hoodwink swathes of gullible people and generate significant income for himself from his "theories" and his expounding of pseudosciences and conspiracy theories. He is a personality disordered individual suffering delusions of grandeur who, upon approaching his 40th birthday in the late eighties/early nineties, realized that he would never become a person of (to his mind) great significance within any mainstream context. He was a household name at the time in the UK from his work with the BBC but his status within the media circles was not a high ranking one.
He had reached the pinnacle of his career from a rational point of view, he had the chance to continue on within such a status quo but that was not enough to feed his ego. The logic goes as follows: You recognize your limitations, you have a need to feed your ego, you know you can never become a leader within an acceptable perspective or frame of reference (e.g. a Prime Minister, Director-General of the BBC, a corporate CEO etc) so to cultivate your ego you invent and conjure up a narrative which (conveniently and brilliantly) places yourself as the head of a movement, sent to heal the world.
He imagined himself to be the "Son of the Godhead" and predicted the impending end of the world in 1997. I think he was clever enough to see an opportunity. He exploited his household status and given the incredulity from the viewing public, he gambled on this becoming newsworthy. It was, his gamble paid off. His nonsense also had an in-built dodge i.e. he was hearing voices and was doing what these voices were telling him to do. As such, no matter how crack pot the ideas were, he would be positing himself as merely a messenger of these crack pot ideas.
He was booked for high profile media interviews, the agenda of which were to (rightly) derive amusement from and to ridicule a man supposedly going insane. That wouldn’t have happened if he was an unknown. He’d have become the local pariah if he didn’t have any status, he’d be that social pariah in the Pub who thought he was a master of the universe spouting cures for the world’s ills who everybody avoided. There was nothing insane about this. It was all a calculated stunt and being publicly ridiculed was part of the process which needed to be endured. Icke was intelligent and sufficiently well read enough to latch onto, and become a proponent for, just about every crack pot theory going at the time. Where new conspiracy theories cropped up, he would latch onto and become an advocate of those too e.g. when The Matrix movie was released, then he would advocate that we’re all living in a simulation etc.
He was the anti-thesis of the Angry-Man Alex Jones personality type. He has this cool, calm and controlled delivery. He sounds smart, speaks fluently, seems confident in what he is saying and his exacting personality lent credence to what for all intents and purposes is patent nonsense e.g. “I have devoted significant time and attention to this story, my research indicates that the XYZ has covered up their involvement in the ABC and, trust me, I compel you to see the truth and not follow so conventional wisdom” i.e. you’re not an outlier, buy my latest book to find out more, book tickets for my seminar to hear more.
He became a brand unto himself and an infamous personality. While the majority of people rightly snub his nonsense, he had the sense to specialize by focusing in on that demographic which is on the one hand, scientifically illiterate and poorly educated while, on the other hand, filled with distrust, perhaps even hatred, of government, science and officialdom in general. Having someone of a high profile speaking out provided a sort of cognitive dissonance for such people e.g. they could be social dead beats but given that there were explanatory conspiracy theories abounding then they could latch onto the strands of such narratives and decide that these theories were the reason they were dead beats and not face up to their own shortcomings.
Such people are sources of income for Icke. Books, conferences, speaking engagements are lucrative sources of income for Icke. All he has to do is pretend he believes in and speak articulately about nonsense such as New World Orders, Babylonian Brotherhoods, Arcons, inter-dimensional reptiles, Illuminati etc while being safe in the knowledge that rational people ignore his nonsense and don't want to waste their time having better things to be getting on with while on the other, deliver such nonsense to an audience whose absence of critical thinking makes them think that watching YouTube videos constitutes "doing the research" while they readily line Icke's pockets who has been mugging off gullible people since the late nineteen eighties. Any significant global event will merely be another source of material and thus income for Icke who perfected the art of being a Professional Conspiracy Theorist. With the 5G roll out happening in parallel with the Corona virus outbreak, Icke must feel like all his Christmases have come at once as it will simply be a case of following his established formula and making significant bank on the back of extremely gullible people.