I think part of the challenge is defining the words we're using.
"Retouching" is not what Ansel Adams called his darkroom work. In my experience, retouching usually refers to removing or reshaping elements of a photograph (usually a portrait) to make the subject look more appealing. In a portrait this might be removing blemishes, smoothing out visible skin pores, removing blood vessels from the sclera of the eye, shifting outlines to make a person look thinner, etc. In a landscape it might mean removing telephone lines from a corner, flipping a mountain, adding or changing a moon, etc.
I think these things are generally not OK, and definitely not OK to hide (pretending the photo was "out of the camera"). Granted, there are certain areas where it is so common (like fashion magazine covers) that complaining about it is like shouting at the tides. But there are other areas, like natural landscapes, where the fight is worth it IMO.
Ansel Adams referred to his work as printing... the aesthetic choices were just part of the printing process. Occasionally they did stray into the realm of retouching; in one photo he burned a hillside unnaturally dark to hide graffiti from a local school. But in most cases he was adjusting tonality, not hiding or removing elements of the photos themselves.
And it's important to recognize in Adams the challenge of capturing the negative in the first place. Perhaps his most famous print is "Moonrise, Hernandez, NM", and in Examples he talks about using his knowledge of luminance values to realize that he could retain detail in both the foreground and the moon in a single negative.
Yes he liked to burn the sky when he printed that image, but it's certainly arguable that that was an interpretation of what he captured in a single negative. I think we would feel differently about that photograph if it came out later that he pasted the moon from a different negative into a boring shot of a cemetery.
Finally, I agree with you that the film context matters. Personally, I am less tolerant of post-processing adjustments to color positive landscapes than I am to black and white landscapes, because of the practice and traditions of so many color-positive landscape masters to "finish the shot in the camera."
Photoshopping the saturation of an average sunset into "WOW alpenglow" values is gross to me; there was a time when the only way to get those sunset colors was actually to be in the high alpine terrain at the right time. Those early photographers created the value of such an image by showing phenomena and places that most people had never seen. Late Photoshoppers are just riding that perception of value.