May a vehicle left as such, in this situation impede traffic or parking for other drivers?

Yes, leaving a vehicle with its doors wide open, as in the picture, constitutes both an obstruction and a hazard in traffic. Open doors significantly widen the vehicle's outline, which can block passage, make parking difficult for others, and also create a danger for passing vehicles or pedestrians. According to Art. 45 para. 1 pt. 3 of the Road Traffic Act, it is forbidden to leave a vehicle's doors open if it endangers safety or obstructs traffic.