Hm. In communist Russia (the Soviet Union, tovarisch! Spasibo.), the sharing was imposed from without, and there was no "ownership" allowed. Without ownership, you lose responsibility. Without responsibility, it becomes someone else's problem and "I'll just use this without any regard for whomever else might need it", which becomes not-good sharing. IMHO.

But you have a good point. When we simplify the rules too much, they become more malleable. Exploitable.

The Golden Rule, in its many forms. The problem with this --well, there's two: one, that you have a difference of opinion on what should be done (i.e., I'm a masochist..)
and two, the unscrupulous will exploit this as they have for centuries. It gets twisted into "Do unto others, then split".

Back to you, o advocate diabolique.