Artifical vanillin is not the whole package though, as there are other compounds in natural vanilla that make up the flavour, so it doesn't reflect the full product. "Natural" vanilla extract may also never have seen a vanilla bean, as it could be plant derived, or even from a beaver's ass.
Until the rise of synthetics the perfect diamond had no flaws or impurities. Now the language has changed and apparently it's all about just the right number of imperfections and impurities, though those will also be mimicked in short order (if they haven't been already).
There is a genuine physical reason to prefer 'real' vanilla extract over artificial. Not so much for diamonds.