Sharpness is to photography what frequency range is to music.
Im not sure, but I think the analogy to frequency is pretty good. However, I dont think it is fair to punish the audience with ear wax, or, to extend the analogy to photography, with a blindfold. Lets assume a happy and unhindered audience, and look at the image a musician or photographer wants to share.
First, when we talk about music,or sound, are we talking marching band or chamber music ?
There is a big difference to the qualities of the sound that either produce. An analogy limps or walks depending how we set the limits, so Im going to come down on the side of a string quartet, or even a duet of some sort. But the fiddle, certainly comes first.
Secondly, Im going to beg you to disqualify the interesting electronic violins being used to such wonderful effect today; this IS an analogue forum.
One of the performance questions that has always been interesting to me has been the process of choosing an instrument that will help the fiddler make the sound he or she wants. We hear a tremendous difference in ancient violins and baroque violins; between modern and contemporary fiddles.
As a listener, I prefer sitting in a small room with the musician to being in a hall with a symphony. Music made for friends is simply more enjoyable to me than in a performance. Whether ancient, traditional, or classical fiddle music, it is more satisfying to me. My own musical friends tend, therefore to share the qualities of music and sound that are meaningful to me - that is the reason we became friends, I suppose. The expressive potential of the instrument needs to suit the player. And then there are bows, one more suited for playing an air than a reel. Most importantly, though, I kinda think that familiarity with a kindred violin might be the most important contributor to the sound made by a musician. A friend and mentor played a good violin for decades and played it in all kinds of weather. AS it warmed up, he naturally adjusted his playing to suit it. As the humidity or temperature in the room changed, he could compensate, and he could pour a range of emotion from it, and even the most technically staid were more than content to sit with him, and listen to the tunes, being washed in the sound like swimming in the sea.
The fiddle was battered, and seemed at times to be falling apart, but it was the perfect instrument for him. My friend was a musician, and an artist. And I mean artist from a very old school point of view, that an artist makes work that gives life. Baudelaire said Art is technique charged by emotion; St. Francis taught that work done by hand was labor, by hand and mind was craft. But done by hand, and mind, and HEART is Art..
Art, therefore, depends upon being fully human, the ultimate challenge of living a life. Perfection depends not upon physical constraints, being rich or poor, but what one does, and how. Technique -certainly- needs to support the art, but never is a substitute.
Thank you. I think the analogy works perfectly. Like music, technical perfection is not necessary for photography.
To come back to the OP's question, "...why so many people are anxious about sharpness?"
I think it is because we recognize, at some level, that making art requires a transformation of ourselves (see St. Francis, above). It is easier to use a perfect machine than it is to face our own limitations.
At least it is for me.
Peace.