I call him with a first name basis because he's probably the person I know best outside my very best friends and my own family. I've been following and listening to him for a decade now and I know his personality well.
Twitter is where he plays around, but his thoughtful personality comes through face to face in talks and interviews. That's what shows how Elon got to where he is. No other CEO talks with the clarity like he does (ironically in a stuttering fashion).
It's not because of a "cult". It's because of his insight into things I had never put that much thought into. He's broken a lot of my own assumptions about how things are supposed to work. He's literally changed how I think as an engineer.