Developement of photography - from science to art
There are two kinds of people in photography. Those who want to take photographs, and those who want to create art. When photography was young, there was only the first-mentioned people involved. It was not in the concept, that photographs could be used in art. Until such people, who also wanted to say something, to create art, found photography interesting.
Pictorialism has nothing to do with art per se. It was an attempt to define what is art in photography, at a time when photography was still new. But art is what we feel, not the tools used, and photography was soon enough (only a 100 years) accepted as a tool to create art thus rendering the idea behind pictorialism useless. So the question is about what changed in photography to make it a tool for art.
Documentary tool begins to see beauty
Think again what was before the time of camera and photographs. It was the time of painters, and especially portrait painters. The first "war" was not between photographers, but between painters and photographers. Painters were making a living from portraits of rich people. It was a painter's moneymaking at jeopardy when photography was starting to take part in portrait business.
One of the painters' arguments was that a straight photograph can not make the subject look any better. That a painter is the only one capable of flattering the subject and make him/her remembered in a favourable way forever, as only painters can twist and turn images as they wish. Photography sought for ways to answer to that challenge, and it is how I see this pictorialism came about. But straight photographers only needed to learn how to make their subjects look good, without "artistic" manipulationing.
Way into grown-up independent photography
..the pictoralist movement as such died in the first half of the twentieth century. Were the straight photographers simply so successful at delivering their message that the pictoralists became irrelevant?
Pictorialism was the way to have photography accepted as a way to create art. In other words, it was seeking acceptance with silent apologies for trespassing into the neighbourhood of art with a documentary tool.
In this case the neighbourhood was painted art. A photograph is so close to a painting as a medium, that a New-kid-on-the-block effect was unavoidable. You have to prove your worth. Like with the portrait paintings vs portrait photographs, in general it is like the painters saying "You can't do THIS" and getting the photographer's answer "Yes I can" and a show-off follows. That's pictorialism, or rather, that's the "Why" behind all else. And there is also the answer to "Why did pictorialism die so quickly?". It happens sooner or later, that the proving phase is over and grown-up photography (along with better equipment and higher image quality) gains the needed self-respect and good enough self-esteem to change the previous answer to "Yes I can, but You can't do THIS!" And what is the This? It is Straight Photography! A pure pixel-sharp image of reality. And so photography becomes a grown-up adult and moves on to live its own independent life with no more need to prove anything.
Old is always challenged by the young
But is pictorialism still here today? Yes, if we think about the younger photographers proving their worth to old photographers. I would not call it pictorialism though. People who have only done digital often can not imagine what difficulties there was in photographying on film. Not so long ago it was (and still is?) the digitals in need to prove their worth to their film-colleagues. The debate between old and new is eternal and what is now new will either grow old or lose the debate and die young.
In photography the key word is "learning". The idea is somewhat similar to Q&A is hard, let's go shopping in a sense that it is hard to obtain high skill and talent to make your subject look good in straight photography, but reasonably easy to go shopping for better equipment and powerful software with which to alter your photographs to fill the gap between a raw photo and your expectations.
What next, photography?
..does the ease with which software turns photographs into manipulated "digital art" mean that the pure vision for straight photography is most important to photography as a separate art form?
Not sure if I understand that. Photography is a form of art, whether it is manipulated and distorted, or plain straight photography. What is digital art, really?
What I consider digital art is something that is so obviously not just a photograph, that anyone can see it. There may be a photograph on which the work has been done, but it would still be considered digital art instead of photographic art.
Two example photos:
This is a photograph. Straight out from camera's memorycard, I have done no adjustments whatsoever. We can call it a "pure" photograph, if we don't count the magic that a digital camera does when it draws the pixel information from image sensor.
This is digital art, done by my 11 year old son, who wanted to give me his impression of the photograph I took of his two-year old sister. Sure there is a photograph there, but obviously it falls to the digital art category.
Is only unaltered photograph straight?
Where to draw the line, exactly? There is nice examples of the power of post-processing under the Good examples of RAW's advantages over JPEG and especially one of the answers with a pair of photos from @EtienneT. Why would the adjusted photo not be photographic art instead of digital art? To me it is still a photograph even with all the adjustments done to it.
Haven't we done this adjusting work on our photographs since the very beginning? Check out this video of making a B&W print where the girl starts at 9:00 minutes with the "original" and explains the "adjustment" process for the next four minutes of the video. This kind of thing has been done forever. Only it is now a computer software to do the job. After all, there is no such thing as unaltered photograph.
Photography turns digital
Now, in the digital age, with everyone a photographer and with technical skill leveled by superb auto modes, does the message of the pictoralist movement resonate again?
Good question. What is the Old and what is the New today? Digital photography is the New-kid-on-the-block, and has been trying to look as good as film photography ever was. But at the same time digital photography is also the Old. Perhaps it is the old photographers getting annoyed with the new effortless (non-chalant even?) way the young photographers approach photography. Much the same way as painters once felt about photography.
When new ways to create art come up, it does not mean that old ways and tools become less important. This is not a zero-sum game.