The original article completely misrepresents the initiative:

We appreciate the passion of our community; however, the decision to discontinue online services is multi-faceted, never taken lightly and must be an option for companies when an online experience is no longer commercially viable. We understand that it can be disappointing for players but, when it does happen, the industry ensures that players are given fair notice of the prospective changes in compliance with local consumer protection laws.

Private servers are not always a viable alternative option for players as the protections we put in place to secure players’ data, remove illegal content, and combat unsafe community content would not exist and would leave rights holders liable. In addition, many titles are designed from the ground-up to be online-only; in effect, these proposals would curtail developer choice by making these video games prohibitively expensive to create.

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Stop Killing Games is not trying to force companies to provide private servers or anything like that, but leave the game in a playable state after shutting off servers. This can mean:

• provide alternatives to any online-only content
• make the game P2P if it requires multiplayer (no server needed, each client is a server)
• gracefully degrading the client experience when there's no server

Of course, releasing server code is an option.

The expectation is:

• if it's a subscription game, I get access for whatever period I pay for
• if it's F2P, go nuts and break it whenever you want; there is the issue of I shame purchases, so that depends on how it's advertised
• if it's a purchased game, it should still work after support ends

That didn't restrict design decisions, it just places a requirement when the game is discontinued. If companies know this going in, they can plan ahead for their exit, just like we expect for mining companies (they're expected to fill in holes and make it look nice once they're done).

I argue Stop Killing Games doesn't go far enough, and if it's pissing off the games industry as well, then that means it strikes a good balance.