I do not understand this. The same third party software is able to extract better shadow details from different cameras. I feel it starts with what the sensor can do.
'What sensor can do'
is the dynamic range of the camera system as I explained above. It's basically constant at any given fixed ISO setting. You may define it in different ways but it will be well defined and measurable.
The amount of 'shadow recovery' and 'highlight recovery' isn't constant, it depends on several variable factors.
Shoot a scene with sky and clouds with some fixed ISO and exposure settings. You get some amount of highlight recovery. Now shoot the same scene with exposure compensation -1 EV. You'll get +1 EV more of highlight recovery and -1 EV of shadow recovery. Now point the camera to the ground so that there's no sky in the frame, the contrast of the scene will be lower and you'll get some more of the highlight recovery. Change the metering mode from evaluative to spot metering and you get yet another amount of highlight recovery in the resulting image.
Now change the software and you may get a slightly different amount of highlight recovery. These are the sliders in raw processors that apply certain (somewhat obscure) transformations to the raw data in your image, they're not a property of your camera system.
You don't measure the camera performance by the amount of so called shadow and highlight recovery, despite of what you can see in some youtube videos/reviews.