I understand that a merge has been purple for a long time and represents a successful event. But closing an issue can either be successful (usually through a PR) or unsuccessful and should remain red.
This change seems rushed and half-baked. Either leave it the way it was, or do it right.
Perhaps simply adding another button to the issue for "Complete Issue" or something would allow users to choose the resolution type. However, I already fear GitHub issues are getting too complex. There's a reason I don't use Jira for everything.
https://github.com/github/roadmap/issues/289
Submitted at the time: https://news.ycombinator.com/item?id=29011123