You are right that using PP software would probably improve the results, but not everybody wants to spend the time on a computer. And I would add that, while even Ansel Adams spent considerable time dodging and burning his photos, digital photography is going perhaps too far in "improving" on the camera's output via PP.
There's always been two philosophies in photography: "get everything perfect in-camera", vs "what you get in the camera is just the start". Ansel Adams clearly fell into the latter category of shooters while someone like Galen Rowell fell into the former category. The choice is yours. Neither one is necessarily "better" than the other, because ultimately, the only thing that counts is the
final image.
The funny thing is, back in the film days if you were to say that you did darkroom work to improve your photo, people would look highly upon that and say, "Oh, cool, you work on your photos in the darkroom! They must look great!" These days, you say you work on your photos in your digital 'darkroom', and some people will scoff, "WHAT? You're manipulating your images beyond how they come out of the camera? That's cheating!" It's really an ignorant double standard. Both are forms of "post" processes. And both are aimed at improving the image beyond "the camera's output". I really don't see why you look down on the notion that "digital photography is going perhaps too far in 'improving' on the camera's output via PP", when photographers have been doing so for decades even back in the film days.