I don't get how you are coming to that conclusion. PS+ subscribers increased 2million since PS4 launch, did you ever think that maybe many of them already have PS+, or were just re-uping their membership? From the article I read on it they don't say these were "new" subscribers, as in their first time. Rather that there simply were 2million subscribers after launch.
My PS+ always expires in November. This year I let it run completely out because there were multiple sales on Plus at the end of the month (Plus for like $30 Black Friday at Gamestop).
I'm not sure were they stand now, but last I heard Live and Plus subscribers were about equal, and this was before Plus being mandatory for online. I would say Sales and Free games do a better job at convincing people.
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