People who take 'blanket statements' on internet forums literally and think they ought to be expanded upon and qualified are taking life (and forum life in particular) too seriously.
IMO of course.
You've created some good debate and have some interesting things to say but on the whole you take things far too literally and seriously for me. This is something I've often noted in people with scientific/engineering backgrounds who are used to having clearly defined parameters to work within and measurable results. The trouble for them when they delve into the creative arena is that art is fuzzy and slippery. You can do something 'wrong' and yet the result works in art. You can let chance play its part and produce art. This seems to mess with the scientific head!
Former cricketer and now writer and thinker Ed Smith once said; "When you play cricket to impress other people you have lost the point of playing cricket." Smith played cricket at the highest level, albeit briefly, so I think that's a sufficiently informed opinion. (His books
Luck: What It Means and Why It Matters and
What Sport Tells Us About Life are good reads applicable to art/photography.)
The concept can be applied to photography and art.
The Tate now purchases photographic works, as do other UK art galleries. Not just works that use lens based media. That is an example of how the perception of photography has changed in the UK art world in recent decades. I've seen quite a few photographs in themed shows of art the Tate Liverpool and round the corner at Open Eye (a photography gallery) I've seen work that was more installation art than it was photography. The edges have blurred.