Excuse my bad english, and the possible misunderstandings
Each software has its own logic and its supporters… This is based above all on the performance, on the habits, on the teaching aids, on the communication - in short on the culture and the common vision that emerges from it… - and on the place that the point of view of certain developers, more or less communicative, has taken.
I’ll refrain from commenting on Darktable, which has its own conception (even if it is evolving, like any product…). The results must be good since “they say so”…
The logic and the process of Rawtherapee are different, they are neither better nor worse than other software, but again, according to the common culture of RT the evaluation will focus on different aspects… In fact, only the result counts.
I recall the link (which is not exhaustive on the subject) Wayne @Wayne_Sutton put , but in RT, Lab is not “bad”, I would even dare to say that in a majority of cases - associated or not with specific algorithms (Munsell to ensure the constancy of Hue when saturation changes) that Lab is a good support (to be nuanced when addressing the problem of high values “absolute luminance” which presupposes an HDR monitor, and a complete HDR process. …which for the monitor is not the case for 99% of the users and for the second point requires evolutions of the management of the terminal process of RT…).
In RT you have the choice, RGB, HSV, Lab, JzCzHz, Cam16, etc… (in main or Local Adjustment mode) and each has its advantages and disadvantages. The main points beyond the dogmas are the ease of use, the final result.
But, important point, I would not launch into a totally sterile debate on these “comparatives” …