He's a banker who made a load of money betting that the economy is fucked. Ever since then, he's started up a youtube channel where, to be fair, he says some interesting stuff. But, he doesn't give any real advice other than "buy assets - that's what the rich people are doing". He talks with a mockney accent so that people like Dai think he's one of them who came good - and if he can do it, so can Dai.
Except Dai's a gibbering wreck of a holocaust denier, can't determine if he lived in Kuwait or Dubai. So, Dai isn't going to become a millionaire watching this Stevenson bloke. But, he can pretend he understands, and pass off his videos on here to get the attention he needs.