@ Denis,,because in those days the thinking was,,protect the cargo,,i.e. stow as much as possible under deck,,nowadays it is opposite,,as much as possible on deck also when above tier 4 usually the container are all empties or very light cargo as otherwise the natural forces during rolling becoming too strong and when damages happen insurance pays.. no worry there.

Why early containerships had very high freeboard? It's like higher than on any modern containership of same length.
Also, what could be that thing on her stem just above the waterline?

A very nice shot of this ship. Best regards, Mike.