Point of information: physical publishing costs have been increasing quite a bit for the last fifteen years, at least on this side of the Atlantic.
Fair enough - as I say, I'm not particularly interested in physical publishing, and I don't know about that industry at all. I was just asked about it in analogy to computer games and mods, so I answered in analogy to computer games and mods. This might be evidence that such laws are still needed in publishing. But I doubt that costs or risks have risen significantly since the 19th century overall. "Quite a bit" could be from a very low base. Again though, I'm not really arguing about physical publishing.
A system of contracts between a multitude of authors and publishers is rather unlikely to represent anything other than what the free market would allow, eh? If publishers can consistently negotiation contracts more favorable to themselves than their authors than that consistency is evidence that the free market favors placing more power in the hands of the publisher.
Sure, given that these rights exist and can be traded on some market, this is
a priori evidence that the price of those rights is optimal. But while a Libertarian might take this as axiomatic, economists would say that it's not at all conclusive. You would need to look at whether abnormal profits were being made in that industry. In theory, a free and fair market in one industry would produce risk-adjusted returns on capital no greater than any other industry in which there was a free and fair market. In practice, there's no such thing; but we can say that industries as a whole shouldn't have risk-adjusted ROCEs significantly greater than the average for all industries over the long run. I don't know whether this is the case in developing computer games in general; if an authoritative source told me that there were no abnormal profits in the games publishing industry, I'd believe them, as it's not obvious to me one way or the other.
Whether the same is the case for mod creators is another story. Do modders get risk-adjusted ROCEs greater or less than the average for all industries over the long run? I'd assume it's less, and would still be less under Valve/Bethesda's licensing scheme. Meanwhile, Bethesda get more profit for little to no extra risk, nor extra capital employed. So within the market for paid mods, it seems like Bethesda will indeed be generating abnormal profits under their licensing scheme. This is evidence that the licensing scheme is unduly skewed in favour of Bethesda; thus the market is not efficient, and the price of those contracts is not optimal.
Having said that, I think we need to go back a step. The existence of specific rights (e.g. something like "the right to modify the assets to this game and sell those modifications") is predicated on those rights being necessary for a free market to function. If that specific right, i.e. the right to modify the assets to this game and sell those modifications, is not necessary -- in other words, if the full value created by the modification and sale of a game's assets is captured in some other way -- then that right shouldn't exist, and the efficiency of the market to buy and sell that right, and the equilibrium price on that market, is irrelevant. For example, imagine if there were a specific right to paint a house green. The right to paint your house any other colour is already included in the price of the house, but for some reason, the specific right to paint a house green is defined separately in the law by statute, and can be bought or sold separately to the general property right of the house. The market to buy and sell that specific right might be perfectly free and fair; the price of that specific right might be perfectly optimal; and the housing market might similarly be perfectly free and fair, such that the loss of the right to paint a house green is already priced in to the price of a house.
But that doesn't mean that there
should be a specific right to paint the house green, as distinct from the general property right over the house. The existence of a free and fair market for a specific right doesn't justify the existence of the right itself. The right needs to be justified first. Is the right to paint the house green necessary for a free and fair housing market to function? No, it's not; the right to paint the house green could easily be included in the general property right to the house, and the price of the house would adjust such that it fully captures whatever value there is in owning the right to paint the house green as well. In the case of paid mods, "the right to modify the assets to this game and sell those modifications" could be (or already is) fully captured in the price of a game; thus, Bethesda can be (or already is) fully compensated for having sold this right. Selling it again via Valve/Bethesda's licensing agreement is pure rent seeking.