There's a long history of clinical psychology and evidence based psychology diverging, with the clinical psychologists adopting methods that actively harm their patients. The history starts of course with Freud, but another prominent example was the theory of recovered memories in the late 1900s.
In this case, the ring theory was developed out of hurt because the first author felt hurt by something a colleague said. That's not generally a good basis for a theory of how to deal with something as complicated as trauma.
Even the basic idea of a "center" is suspect. In many cases, a traumatic event is an event that affects multiple people who must interact. The classic example of trauma is warfare. Families go through trauma. Even when there isn't a common trauma, many conversations happen between individuals who have separate but comparable traumas. You don't want to get into a frame of mind where you have to judge and compare people's trauma to determine what they can and can't say.
On top of that there is a lot of research on kvetching and whether it's good for patients. In most cases I'm aware of, it's harmful to them. Most evidence-based approaches, such as Cognitive Behavioral Therapy (CBT), advocate the opposite of what this article is advocating. CBT says that the patient does best when they talk back to their own distorted thoughts. That means not thinking of yourself as the center of some universe, and not thinking of yourself as a "why me" victim that is targeted by some cosmic force. This article is saying diametrically the opposite; it says you should reinforce people's distorted thoughts.
Of course, you have to be kind and gentle to someone when they're having a hard time. But that kindness can take a lot of forms, and this article is advocating a very particular and almost ideological approach.