These "discoveries" are not the first discoveries during the cutting of an unknown tissue, and discoveries such as those that have escaped the eyes of physicians for centuries. The entity is an alteration of the terminological definitions of already known constructions. They are, therefore, terminological determinations rather than a physical finding.
The announcement of the interstitium as an "organ" is similar to the classification of an already known mesenteric intestinal hook as an organ over the past few years. The mesentery is a peritoneal extension that connects a portion of the intestines to the posterior wall of the abdomen. Da Vinci said that even from the time of his drawings, this tissue, known to exist, should be classified as an organ from 2017 onwards. As you can see, there is no new discovery.
The interface is already roughly "intertextual space". It contains interstitial fluids and lymphatic flows. They help many physiological processes. In a study published in the journal Nature, interstitial space associated with the biopsy, submucosa, from extrahepatic bile ducts was observed. In other words, it is understood that these areas are also present in the bile duct outside the liver. Normally there was already anatomically known existence of this structure. In this study, it was observed that there were anatomical structures directly supported by connective tissue. Because of the new endomicroscopic laser (pCLE) biopsy technology, the structure of the tissues can be protected better.
As you know, in pathological examinations, the tissues are cut through a number of procedures and examined under a microscope. Naturally, artefacts from the cutting process can create many good or bad judgments. This makes the terminological categorization of various structures difficult. With this new method, it can be understood that this structure is not an unwanted artifact arising from the cutting process. Thus, this anatomical structure could be categorized as an organ.