I'm pretty psyched that the PS4 looks powerful as far as the hardware is concerned, but then so is my Vita and we all know how that is turning out. How can Sony make things better with the PS4? Wasn't PS3 more powerful than 360 this gen and didn't it consistently have underperforming multiplatform games? Won't we see another "least common denominator" scenario with PS4 and Durango?
In summary, if Durango is almost as powerful and 100 cheaper than PS4 (speculation) - is what I love about Sony's hardware right now going to look like a mistake?
1. The price difference between PS4 and Durango won't be significant if MS is even in the same ballpark hardware-wise.
2. The PS3 had more theoretical processing power, less memory, and far less dev friendly tools and architecture. This is why games made specifically for the system shine. Next generation "least common denominator" will still allow for significantly more scaling, as both will be running more more similar architecture (AMD CPUs, ATi GPUs, etc.).
3. The Vita is struggling because the dedicated handheld market is all but dead outside of Japan, in decline there, and it costs more than what consumers are comfortable spending on a uni-tasking portable device. The PS4 is aiming at a market segment that grew last generation, has done nothing but grow for about three decades now, and where a bit higher premium for high end hardware is accepted.
4. Sony's first party studios and IPs are heavily focused on the home consumer. They have little mindshare with the handheld specific gamer, they have several strong brands on their consoles that compel users to buy systems.
5. 3rd party support for the next PS4 is guaranteed, it's anything but that for the Vita.
6. Sony's commitment to the PS4 will be on an entirely different level from the Vita from a marketing standpoint. The PS4 will be pushed heavily.
Ultimately your theses also boils down to a logical fallacy too, by the way. How are two products with incongruous target audiences supposed to predict the likelihood of success for the other? By your logic Apple should have never released the iPhone because they weren't a strong contender in the whole "personal computing" market via their laptops. Not only did it work out well, it strengthened the laptop brand along the way.
The same could well be true for Sony. A successful PS4 will have an echo within PS Vita sales and developer support, especially if the PS4 becomes the dominant home console in Japan, even despite the shrinking audience there for a home console.