I don't think the average HN commenter claims to be better at building these system than an expert. But to criticize, especially critic on economic, social, and political levels, one doesn't need to be an expert on LLMs.
And finally, what the motivation of people like Sam Altman and Elon Musk is should be clear to everbody with a half a brain by now.
They claim to serve the world, but secretly want the world to serve them. Scummy 101