So what, they all had computers simulating atmospheric flights even in space, to make it less confusing for the pilot? :).

Sure. Let's go with that. :)

There's actually a space combat video game which tackles this issue head-on called Void Destroyer.

You can pilot your spacecraft in "easy" mode, where it goes in the direction you point it. However, that severely limits its speed. You can also set it to be in full 6-DOF mode (like the Descent video game series), but that takes a lot more practice to do well, and frankly, the interface isn't suited to that. Mostly because with Descent, you are inside a cavern, so that you maintain a good sense of where you are and what direction you are going. That doesn't work as well in outer space, with less "landmarks".

https://store.steampowered.com/app/259660/Void_Destroyer/

Having both sides agree to that and not cheat would be an unprecedented amount of coordination; you could probably write a sociology paper just from this observation :).