For a CFO position of a publicly traded company, 34 years old isn't a kid--it's practically a toddler.
But the bigger issue is that he simply doesn't have the experience that would be expected of a CFO of a publicly traded company, especially one that employs so many non-standard accounting metrics.
But the claim is age means he can not be good, then when shown example of young CFO you claim cherry picking, but leave out the possibility that he could also be of the same caliber.
I'm not saying that his age means he can't be good -- David Knopf is the perfect example of a qualified young CFO.
But David Knopf is also the exception that proves the rule--before becoming CFO, he spent almost a decade earning experience doing exactly the kinds of things the CFO of a publicly traded company would do. Similarly, with the other examples cited, they all had direct experience doing the things that the CFO of a publicly traded company would do.
But no one knows anything about the new CFO of Tesla. If he had been involved in Tesla's compliance or public-facing finance functions prior to this point, someone outside of the company would have worked with him and vouched with him. The silence speaks volumes.
But the bigger issue is that he simply doesn't have the experience that would be expected of a CFO of a publicly traded company, especially one that employs so many non-standard accounting metrics.