Amongst his big pile of failures, his two real successes (EVs and specifically the Falcon series of rockets) were also things people dismissed as announced, and in some cases continue to dismiss.

Unless you're counting the ongoing dismissals of those as examples of "they lie for their own advantage"?

On the other hand, while every brain scientist I've heard dismisses Neuralink, every civil engineer dismisses TBC, and bluntly the shiny prospectuses for each of the moon based factories and the Earth-based Optimus factories are on the wrong side of the laws of thermodynamics, I was surprised to see Solar City's roof shingles fail in the marketplace.