Are we to continue to maintain that the intended goal of copyright is the protection of the rights of creators? Or is it a tool to give incentives to create?
A commonly cited goal of intellectual property lies in the claim that creative works are able to be “owned” by those people who helped make it. This is the approach entrenched in the International Covenant on Economic, Social, and Cultural Rights at Art 15(1)(c):
The States Parties to the present Covenant recognize the right of everyone:….
(c) To benefit from the protection of the moral and material interests resulting from any scientific, literary or artistic production of which he is the author. [in this context “author” has a broad meaning. It can include groups, and can easily include the creators of a video game].
Usually, the argument takes one of two forms: One of natural rights to property, according to which the labour involved in creative work entitles the maker(s) to monopolize the exploitation of their work by right, and one of utilitarian concerns of the advancement of culture and science, and the desire to grant incentives to develop these areas. So the basic split here is "Do you grant copyright because it's fair?" or "Do you grant copyright because it's good?"

Those who advocate the former approach to IP policy- the view of IP rights as fundamental rights rather than privileges- the notion of copyright being applied to works where the creator cannot benefit raises questions of quite how that copyright can be justifiably continued. In other words, if copyright is the Human Right of the creator, yet the creator cannot benefit, where does that leave copyright? Just as Tolkien won't be writing any more Lord of the Rings books because he's dead, Bullfrog won't be making anymore games because they're closed. And yet copyright persists in another entity. Whether or not this is fair and just is something the copyright debate must grapple with.

For those of you who prefer the more public policy minded approach, consider Article 1, Section 8 of the US constitution:
The congress shall have the power to... promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries
We also have issues. If the promotion of science and useful arts- both of which, I would argue, can be greatly influenced and advanced by games- is your goal, then where does copyright fit into a situation where a game can no longer provide an economic benefit to those best placed to turn this "exclusive right" of copyright into future advances? A closed company won't be spending anything on development, regardless of how much money its products continues to make. This leads us to the next question...

Are we right to support the continued privatization of these works long after any claim of incentive to create has vanished?
The Preamble to the TRIPs agreement -currently the key international treaty regarding intellectual property law- describes IP as a "private right". This is true enough; the concept of copyright works by granting holders of IP rights legal monopolies to exploit their creative works. The modus operandi of copyright, regardless of its aims, is to privatize culture, at least temporarily. But in a world where 10 or 15 years is enough for the economic benefits of copyright to become redundant, how do we justify granting copyright that extends way beyond the natural lives of its creators?