It won't need higher pc specs to run, at the end of the day all your pc is really doing is running a series of pre-rendered images. If anything it's Ren'Py's code and how optimised it is that will alter that.
However with DPC, he basically works in the same way as new roads. Namely that much like how building new roads lead to more cars journeys and therefore no change in congestion, DPC upgrading their machines sees them add yet more details which require more computing power so in the end don't save time.
A great example is their move to 60fps animations after upgrading to 30 and 40 series GPUs, which meant development still finished well in advance and spent weeks at the end simply waiting for animations to render.
