That may be true for some high end jewelry/watches but you can't make a blanket statement like that.
Sorry, you are absolutely right I didn't mean it to come over as a blanket statement, I apologise, but you have raised excellent points for conversation.
As regards your link, there are some interesting images on the web site along with some interesting statements.
"there is almost no way you can deliver an outstanding shot by using an "as-is" image. Of course, some subjects do not require much of post-production, but every photo shot needs to be "polished" to make the product look like a million dollar piece."
I do note that they say "almost no way" and indeed I have many images land on my desk that only require a small colour tweak or grey balance adjustment and a little sharpening to make the depiction accurate to the product which is what many of my clients require. There are still a majority though who "want the product to look as good as it can" irrespective of what the actual item looks like.
Does highlighting the facets on a diamond within a ring constitute enhancement and hence giving a false representation of the crispness of a product. Would this be classed as being "polished". While not creating the facet you are making it look better than the original.
Getting back to the initial question here is how I would see it. If a single mark/blemish created in the making of a product has been removed from that product or a particular feature highlighted beyond how it would appear in person then that constitutes enhancement and that makes the picture "better" than the product. This still means that my answer to the original question is still yes, a photograph can be "too good".