>individual ownership of the means of production is arguably the default state. //

Could you flesh out that argument because I'd imagine that co-operative ownership was essential to the rise of civilisation.

Tool use age by various animal species is generally used by the individuals that locate and or create the tools. Similarly the defense of hunting territory by individuals or families is another means of production. Complex social structures and collective ownership are very much the exception.

In very early stages, yes. Until humans figured out that ownership can be concentrated by using violence.