lenses that can achieve a narrower field of focus are the more expensive ones, so there is established artistic value.
I'm not really taking issue with your conclusion, but a decent quality 50mm lens (widely known as a portrait lens because of its shallow depth of field) can be got new for about $200. And I got a beautiful 1984-vintage 105mm prime lens for $250 a few years back. It's an exception to the rule, yes, but sometimes the glass is less expensive than the camera body. That said, if you've got good lenses, they can make up for a lot of shortcomings in the camera body.
My own feeling about algorithms such as this is that they'd be better off chasing the ideal of perfect focus for everything - or better yet, for pseudo-3D renderings - those would be more desirable goals, IMO. I suppose it's possible to get the same effect as really good glass, but something tells me the laws of physics (well, optics) will always win over computed logic.