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God of War Ragnarok will require a PSN account
(programming.dev)
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But you could come up with a believable reason for multiplayer. (Ex. Maybe the devs decided their servers wouldn't scale and had to move to Sony's, but those require users to have a Sony account.)
For single player, there's not even a hypothetical excuse. They just want you to be inconvenienced for their own gain.
My guy, the PSN requirement was suspended because it was causing server issues. You can use it RIGHT NOW without PSN...
There is no believable reason, that's why users were upset.