I am reading up on Clarence H. White, a photographer and teacher of some note from 100 years ago or so. White was rattling around New York City about the same time Stieglitz was holding court there, and they overlapped and interacted a fair bit. They ran with the same gangs.
The attentive reader of history will, eventually, notice that the main thing Stieglitz seems to have done was fall out with people. He also ran a couple iterations of a small but evidently influential gallery, and he published an influential magazine.
Now, I get that if people say a fellow is influential, well, then he is, because influence is entirely about perception. Still, Stieglitz doesn't seem to have done much except sit around writing and judging (the irony does not escape me, here).
White ran a school which churned out a number of truly stellar photographers, and a few handfuls of B-listers (known, but not, you know, well known) and White's influence is felt literally to this day in advertising photography. But White practically does not exist in our historical understanding. Beaumont Newhall, shamefully, almost entirely omits him from what is the standard American history.
Edward Steichen was a curator of real note, held the post of Director of Photography at the MOMA for about 15 years, curated The Family of Man, and a bunch of other stuff. Newhall, at least, and I think our collective grasp of history, consigns him to the role of a kind of Stieglitz protege.
Stieglitz, on the other hand, seems to have been born a grumpy old man with too much money. His usual reason for falling out with someone was that the someone was too mercenary, not committed enough to photography as a pure art, but rather decided to make something commercial of it. The effect of this is that he had no patience for photographers without money.
It is long past time to correct the record, I think. Not by minimizing Stieglitz' role. His role was real, photographers did go to him to pay court, and his imprimatur was valuable. Rather by enlarging our understanding of other roles. To whom, for instance, would you go with your Letters of Marque from Stieglitz (who had, himself, nothing by those Letters to give)?
White, Steichen, and (ugh) even Newhall, among surely many others, were the people who could actually redeem Stieglitz' grudging approval with concrete gifts. Exhibitions or, gasp, jobs.