This is the way the building was built in 1911, yet in the 1950's and after the situation changed. My guess is that the station changed because transportation did, and also because of the communism here. The station was separated into different areas. As you walk up the stairs from the bottom level, the area to your right (as you reach the landing point) was blocked to create an extra area for the restaurant, and the waiting room was blocked, so access was only from the platform. This really changed the flow of the station.
Things probably changed a lot after ww2, more transportation by trucks and cars. So the station was separated and the different parts managed from a distance, probably?