> I think the first action suggested was to unbuckle your seat belt

As long as you are oriented. This may apply more to bigger vehicles that have turned upside down or are sinking nose-first or whatever. It can all become unfamiliar. You may need to actively figure out where you are and what route you are going to take out.

For example, I have a 3-door car. Someone in the back seat might need to escape through the front passenger windows. I think the STOP acronym applies. To get out fastest you need to be efficient, and to be efficient you need a plan. Especially if there are other passengers in the front seats.

Anyway, the point is, if you are strapped in your seat you know where you are. You can remember where other things are in relation to you, even if up is no longer up.