>>2851113Because the sensor infrastructure allows you to exposure differently than a non-isoless one. A photo shot at iso 800 on a Fuji is indistinguishable from one shot at 200 and bumped to 800 in post. The benefit is that it allows you to get a jpeg without blown highlight immediately.
If you don't understand it, it's not your job to. You'll get it by experience if you ever handle the cameras and files.
Pic related is iso 800, DR 400% jpeg
