They won't , thats why nobody has tried to make a DCS truck sim. Please explain to me how this would be more realistic then ETS 2? Have you SEEN the ground textures and building placement in DCS?
Its not about the cockpit its about the world. DCS looks like shit on the ground , and even with EDGE it still wouldn't be good at all compared to ETS. A fancy cockpit alone doesnt make it a good truck sim. And ETS's cockpits look fine. The(edit : there are other simplified things i suppose) only thing thats unrealistic in ETS is the distances , but who wants to drive for 24 hours or however long a delivery would take in real life , anyway?
I can't really tell if you're joking or not... get real please.
Next up you're gonna ask for a metro simulator within DCS , DCS isnt some universal engine in wich all future simulators should run.