>but in general it refers to a style in which the photographer has somehow manipulated what would otherwise be a straightforward photograph as a means of "creating" an image rather than simply recording it.
I don’t know that sounds exactly like the Instagram and Snapchat generation to me.
That's a description of pictorialism, which the original comment is saying has won over realism.
Group f/64:
In part, they formed in opposition to the pictorialist photographic style that had dominated much of the early 20th century, but moreover, they wanted to promote a new modernist aesthetic that was based on precisely exposed images of natural forms and found objects. (wikipedia from OP link)
f.64 wasn't exactly about realism, either. Black and white film (though they didn't have much choice). Burning and dodging to add drama. Depth of field way beyond what eyes would perceive.
Your eyes adjust focus moving from object to object, so you won't see defocus the same way a camera will. If anything, things will usually look sharper with your eyes.
I don’t know that sounds exactly like the Instagram and Snapchat generation to me.