Tim Dillon said summarized it pretty well - can't remember or find the exact quote. Something to the effect of:

"Look around at all these things I have - how could I be wrong when I have so much?"

And that's how you get the Andreessen's and Musk's of the world stating these nonsensical things as truth. In their minds, financial success is the ultimate yardstick. The fact that they have so much wealth is a testament that their way of thinking is always right.

You don't need to look very hard to see this is what they really believe. Elon has done extremely silly things like claiming he was the best Path of Exile player in the world because he paid several people grind his account to a high-level. Having enough money to pay someone to play the game for you, is the same as being good at the game, in his mind.

What I took from the video game thing is that he thought he could fool people.

It's very obvious to gamers when someone hasn't played, it actually doesn't matter whether you have high level gear.

There's things you can't buy with money, and respect is one of them. He fundamentally doesn't understand how status works. He could, for free, just put out a video where he says "look at me, I'm a busy CEO, but I play this game even though I'm bad at it".

People would think positively about that.