Do lenses have to be razor sharp to create interesting images? No! Thus do images, by extension, have to be sharp to be interesting? Absolutely not, indeed sometimes by preference not. Plus what is sharpness anyway? It is after all a perception and not an absolute and thus subject to interpretation.
So why this modern gear head obsession with sharpness? Well it most probably stems from the marketing divisions of the major photo equipment manufacturers where the higher the numbers associated with their products the better they can differentiate them from the opposition and the more they can charge. You know, the most megapixels, the highest ISO, the sharpest and fastest lenses etc.
This in turn leads to owners bragging rights. Owning the best (read the the one with most of something) products in the market, which in case of lenses are the sharpest or in case of the camera/lens system the ones that produce the sharpest images.
But what if your lenses render, as many modern ones do, images that seem overly sharp or too clinical or lacking in character as they are often described? What if your artistic intention is to render your images with a lovely soft glow and a more gentle transition between the edges of the objection within the image as in the picture above? Then you need lenses that draw in a more classical way than these modern aspherical designs but where now-a-days do you find them? What then of your boasting rights of owning the sharpest lenses on block, its all irrelevant.
This brings us nicely to the image above. Taken on Zeiss Ikon loaded with Portra 400 with a C Sonnar 50mm f1.5 wide open. The question arises, is it sharp?
Well had this been rendered digitally with a modern aspherical lens like a 50mm Summilux say on an M10-R the answer would have been an emphatic no. The image from the M10-R/Summilux ASPH combo would have been ultra clean, ultra sharp with extreme delineation between the edges of objects within the image, providing that banal modern look i.e. cold, super-clinical and boring.
Ask the question again of the picture above, given that the image was drawn with a classic style lens used wide open, renowned for its creamy bokeh with rounded sharpness plus add in the shallow depth of focus from being used close up and wide open and the answer is a firm yes, as far as the bits that matter that is. The image is provided with a beautiful, glowing, organic, romantic feel to it very much in keeping with the subject and the era from which it came. This lens was exactly the right one for this subject.
Thus being obsessed with how sharp, whatever that means, your lenses are is really an unhealthy thing; better to understand how your lenses draw and use their qualities to best advantage and above all be obsessed instead with light, thus mastering photography. Remember the old saw, “Amateurs worry about equipment, professionals worry about time, masters worry about light”.