That is a common misconception. Many pro photographers will tell you that the Lens is greater than the sensor when considering photographic equipment. In fact the sensors on many SLR cameras remain pretty much the same with small enhancements here and there on each iteration. Just google "what is more important, lens or body" and read the hundreds of people asking the question. The general consensus is that Lenses always comes first over body.
Have you ever used focus on a camera / projector? Sharpness is affected instantly. Also, If the lens is not perfect across its entire surface then focus will be off, if focus is off then sharpness is off too.
We know that the Pimax lenses exhibit issues in the v5 so they should work on that as well as trying to tweak the panels, but that's probably simple calibration in software. They have FULL control of the optic design and need to get it nailed as much as they can before shipping. Software can be tweaked any time after it has shipped, they could even add E-Shift technology into the scaler driver to give a sharper upscaled image for instance.
You are thinking in TV/Monitor terms where a wider colour gamut mostly defines sharpness. You need to also understand what sharpness is when adding a lens in the mix......here read this article.