My understanding of SKG comes entirely from watching the EU deposition, so take this with a grain of salt, but I lean towards agreeing with OP. There are other points of contention for SKG than just 'this doesn't apply retroactively'.

SKG is concerned with:

• Making sure games remain available to the consumer and do not die at the whims of the publisher
• Allowing alternate methods for communities to stay alive (such as private servers)

Just because the game is being kept online for another year, does not mean that it will be purchasable after that. In my view, publishers should take the GOG games route and allow their games to be kept DRM-free if they decide to stop support. That way, the game can be circulated amongst friends and enjoyed for years. I am not sure of the specifics of the plan for this game beyond the article though.