I bet the fifth picture - the Hammertime freefaller - is included to demonstrate that falling aircrew don't automatically assume the 'modern' skydiving posture (because some people said it is unhistorical a week or two ago.). Although, MC Hammer is equally anachronistic
Oleg and 1C are in a terrible situation. Whenever they work on the sim, they can only increase the ability of the community to nitpick. The more details they include, the more anomalies the community will spot and loudly declaim. Every added feature presents three new features to follow after it, and the community will ask for all of them and claim to be insulted they're not included already. It's a paradox - the better the sim gets (and all their work does make it better!), the more the community will find reason to complain!
***I'm not saying it's wrong to point out discrepancies (I do it too!) - in fact it probably helps Oleg&Co. to make the sim better. I just think this paradox is interesting/tragic/amusing***