This is directly copied from the Developer Diary part 1:
"15) Do you plan the level of graphics cockpits like in basic models in CLOD (Spitfire/Bf-109)?
No. You will not see this. The reasons are simple. The creation of one such cockpit takes a year, sometimes more. The popularity of the genre has to be phenomenal for such expenses were justified. If we are not careful, the budget ends and with it the end of the project. It is also not too wise to use more PC than necessary and use twenty textures, where it was sufficient to use three. Not being smart with resources can result in serious performance problems. We hope to find a balanced solution. Good performance with nice looking cockpits."
That could explain why the cockpit in CLoD looks a bit better.