@anon41087856’s many references replacing module X by the color balance module in his Darktable 3:RGB or Lab? Which Modules? Help! article need to be seen in context of that article. Can the color balance module replace the tone curve on its own? No, I don’t think it can. But in a linear RGB workflow it can because it is part of this whole rgb exposure-filmic-tone equalizer-etc modules toolchain.
Most people don’t like change and rather stick to what they know and/or have experience with. I’m no different, but sceptical as I was I did jump on the linear RGB bandwagon (kept falling of a few times, too) and am now convinced that it is a way of working that I really like. I don’t understand all of it yet, but that path is part of the fun.
I almost wrote and am now convinced that it is the better way, but I think as long as it isn’t your bread-and-butter having fun editing is more important than this being the better/correct way.
I never went into this experiment looking for or expecting to find replacements for any specific module. Now that this exercise is finished I’m confident that this specific module lives up to the claims put upon it though.