This is a mod.

In the original game, flight is limited to space and is very arcade-y. Press ‘W’ to activate thrusters and move forward.

KSP, Flight of Nova, Elite: Dangerous - there are plenty sims out there catering to those who want realism.

I think that forcing a completely realistic re-entry would be a bit much for most players, though it would be awesome for the option to be available to those who want a hardcore experience.

At the end of the day, most games are more enjoyable when you suspend disbelief. This is a game where people wear spacesuits in a vacuum, get shot multiple times with blood effects, and carry on fighting without experiencing violent depressurization.