They had configurable execution order and masks well ahead of everyone else (back when lightzone was still commercial) and the interface was always straight forward. Some things are just much easier to achieve with reconfigurable orders. For example desaturating an image and then adjusting the contrast curve of the black and white photo. I just tried that in ansel and you can't do it because the desaturation is done after the tone mapper. You can probably achieve the same result but it's just more difficult.
I find that darktable (and ansel as well) suffer from too many modules touching the same fundamental things. E.g. There seem to be several modules that adjust the color calibration white balance, exposure. So I have seen multiple times that I get a very bad initial look, but I can't fix it easily with e.g. the white balance without turning those other modules off.
I think OP was pushing for the scene-referred workflow and removal of the legacy display-referred workflow and all related modules. In fact Ansel made a step in that direction. It removed legacy modules (from UI at least), also, for example, it replaced sharpen and soften modules with some iirc wavelet-based thingy which does both (I forgot the name as I tried it long ago).
Can’t comment on contrast after desaturation directly. Perhaps OP could explain why it is done so. A tangential thing: desaturation is actually a complicated process. You could rely on lightness, you could rely on RGB components, etc.. I think Ansel and its Color balance and CAT modules give you full control over all this complexity. These tools are much more flexible than anything offered by competitors. But it’s certainly not easy. This is a bit related to the sibling comment about targeting towards technically inclined people.
There's an effort underway to recover the original web site, but the domain name owner disappeared a while ago, which complicated things.
Agreed on the paradigms around stacking / ordering & non-destructive workflows used in Lightzone. It's my preferred photo touching-up software for similar reasons.
We have Lightroom, we have Capture One. Let one software for more technically-inclined photographers exist, where you have options and power over the pipeline. Darktable does not aim to be a Lightroom replacement.
I accidentally put words into OPs mouth. Not fixed module order, but correct module order. But even if OP argues for the fixed order, I would trust him fully on that. From what I recall, one of his arguments was that different modules work in different color spaces. And it does not make any sense whatsoever to feed linear RGB into a module that works in some perceptive (logarithmic) space. A car owner who installs 4 different-sized wheels on their car is not technically inclined, he’s just an idiot.
FWIW, in my 2 years of using DT, I never needed to reorder modules. I mean, I used to play with that in the begining. I would spend 4 hours on a single picture reordering modules and doing all the crazy stuff, and then eventually I would start over because the pipeline becomes unmaintainable. I just don’t see, how this can be any useful if your goal is being productive and not just fooling around with your pictures.