Without going through the previous post point-by-point, I’ll offer this:
Tonal compression is [almost] always required; and it has been the case that compression of the tonal ends
has been considered more desirable than in the mid-tones (though how much this stance has been influenced by the inherent sensitivity characteristics of silver halide film and papers is open to debate). I recall reading many years ago (as an amateur since the early ’60s; a student for three years in a very
technical photographic course; commercial photography since the mid-’70s; and more recently a user of computers for imaging over twenty years, I do have some form) that compression of highlights and shadows is visually preferable to that of mid-tones. It’s all a compromise of course.
On posterisation, if I understand your point correctly, I was [perhaps not effectively
] trying to say that compensation in one part of the tonal range can lead to problems in another area. Particularly with curves; when I taught graphics as part of a multimedia course, every year I advised students to use Levels rather than Curves in Photoshop for the reason that it is harder to cock-up Levels (and the histogram is very useful too of course).
Talk of HDR is moot if the tonal range thus produced is still wider than the media it will be delivered on. I find most so-called “HDR” to be ugly, heavy and over-saturated in darker areas. Sometimes, you need
a cloudy-bright day to get a pleasing tonal range where detail and texture is maintained at the extremes. Or make a aesthetic decision to lose some detail to reinforce a mood; good example of H/L blowout here