In some cases whole population of a country may behave as a single group. Let's say USSR at 1941 was clearly one single group focused on "do everything for the victory".
As of the humanity... Global warming and other global threats will group us all.
That's a very good example of a case where people were not acting as a single group at all. Most of the soldiers were simply leaving everything and retreating, because at first they were not sure if Hitler was really worse than Stalin (http://www.solonin.org/en), groups of people were joining with German army sometimes hoping to get rid of soviets and sometimes because wanting to kill neighbours (e.g. https://en.wikipedia.org/wiki/Stepan_Bandera), food was being captured from all the areas that potentially could end up under German control, which ended up causing the famine in Leningrad. So even if from afar it looks like a single group, it was much more complex and turbulent close up.
This is only true in some kind of socialism, counterexample: mutalism.
"social ownership of the means of production"
Social ownership: can be public, collective or cooperative ownership, or citizen ownership of equity.
The problem with all of this, is that if someone works better than others, and creates his own "means of production" there must exist someone else who will seize it and distribute it to the collective, otherwise the means will again concentrate at the hands of lucky or more hardworking people.