I wrote something about this in my post about open platforms.
For anyone concerned about preservation of the medium, closed hardware and software platforms (and worst, both) are terrible. What's even worse are streaming-exclusive games -- luckily this hasn't happened yet.
Preservation
For any serious medium (and fans of that medium) preservation of classic experiences is an important issue. Think about the collective loss for all of us if any books or musical compositions older than 40 years were no longer available, or only readable or available to listen to with lots of effort and highly specialized equipment.
Games are unique in that they are interactive, which makes their preservation significantly harder than anything that can simply be recorded and played back. To experience an old game on a proprietary platform, you need a working instance of that hardware platform, its accessories, and the game, as well as all the other devices (such as displays) from roughly the same time period so as to be compatible. Already today, the most convenient and viable way of playing old classics is via software emulation, usually on open platforms. However, modern hardware-assisted DRM schemes, highly complex hardware/software architectures and slow down in the progress of sequential CPU performance may make emulation an almost impossible task for current and future platforms.
Conversely, games on open platforms are usually compatible with a wide variety of hardware, and over long periods of time. Even if a point is reached where no directly compatible hardware is in circulation anymore, emulation is usually greatly simplified by documentation and a lack of hardware-level DRM schemes.
For anyone concerned about preservation of the medium, closed hardware and software platforms (and worst, both) are terrible. What's even worse are streaming-exclusive games -- luckily this hasn't happened yet.