I like your post, and would add one more that I think should be an addendum to every discussion of copyright in the current context:
(4) Without any empirical data showing that current copyright expenditure is lower than the optimal level.
The purpose of copyright is to make our world a better place by rewarding creatives for an activity that the free market cannot naturally price. We choose to create artificial scarcity to establish a profitable market for creative work. When the government steps in to create an artificial market, to set an artificial price, it is a necessary function of the government to seek to set a price that is market optimal.
The degree of copyright enforcement, strength and duration, is how the government establishes the artificial market price. In a perfect free market, that price naturally reaches the optimal level through competitive supply and demand. In a government established artificial market, that price must be consciously selected. We are not making that selection based on empirical data or market measurements. At present, we are blindly accepting the labels' supposition: "More, because we say so."
Do we need more culture? Are we Sparta, powerful but lacking in a cultural record, or are we late Rome, growing weak because of excessive expenditures on entertainment and cultural excess? If the former, we would make our society better by increasing copyright strength and duration. If the latter, by decreasing it.