the Xbox Console market would be maybe dead but Sony has exclusives. If you could have a stronger PS4 to match PC gaming in performance and you would have awesome exclusives like Bloodborne or Driveclub what would be the point for PC gaming?
No, it would be silly, would just be a Market Eating another Market, and disguising if it was the Market it ate, would just be The PC, market and a disguised Death of the Console Market, would split user base and the most important, it would piss developers, Developers don't want power, they want Money, and they can get it with PS4's Current level of performance.
Xbox, already confirmed a Upgradable Hardware, and their exclusives for PC, because of that they are falling behind and struggling to keep the same pace they had last year.
Sony, know this and won't will do the same, a Deny, would means nothing, they would need to say what they are making, if they announce a Cheaper PS4 Slim, now, the people would stop of purchasing PS4, until the cheaper one cames out, if was a More Expensive Product (of course if launch with those Specs, will be 600-800US$), this would not eat PS4 Sales, because would be Niche, this would piss the Install Base, and Sony, would lose a lot of Money.