the fundamental way of tea will die out.
on the contrary, that it is flourishing.
when it becomes completely
a matter of worldly amusement —
is now in sight.
— Sen no Rikyu, 1589 
It is likely that he was considering both the intangible and material aspects of the enterprise that became Cha-do, the Way of Tea. Compare the aesthetics of his tiny, still extant Taian tearoom, dating from 1583,
at Daitokuji in Kyoto and Hideyoshi’s long-gone portable Ogon Chashitsu (golden tearoom), created in 1585 and eventually destroyed in the Osaka Castle fire of 1615. Dare we infer that Rikyu, a Zen monk, was attached to the idea of this “fundamental” chado, not that Way of Tea? Perhaps, but his signature notions of wabi and sabi—well worn, essential, imperfect, quiet, and impermanent objects—has reached us to this day through 16 unbroken generations of Senke Chado practitioners.
The history of chanoyu and its impact on Japan is long and anecdotes abound as a result of practitioners’ keeping meticulous diaries of who came to tea, what dogu were used, the meals served, etc. In 1757, the term iemoto  (grand master) became fixed as a cultural norm for these families. Paul Varley notes, in Tea in Japan: Essays on the History of Chanoyu, two reasons that this system caught on formally. The first, “... a swelling demand for the arts” largely from amateurs practicing chanoyu “as an avocation or who wished to enrich themselves culturally”. Successive generations of iemoto cultivated new, innovative ways to take advantage of Japan’s social, cultural and economic shifts by adjusting the practice, for example by creating procedures requiring formerly never-conceived dogu, such as tables and chairs! Of course, students required more lessons to learn these new ways.
As in the tea schools, the responsibility for carrying on the artisanal traditions have been carefully passed down, usually from father to a son (though currently three holders of lineage are women) chosen for his/her technical mastery of skills, as well as his/her capacity to sustain the lineage by maintaining its material resources. Producing and training an heir, a wakasosho (young master) is essential. In addition to the land on which the workshop stands, the inheritance includes in situ sources of raw materials and caches of those that require long aging periods (e.g. clay, drying timber), proprietary patterns and designs, and notebooks (including records of how and when objects were used), fabrication tools, pattern books, models, molds and equipment (such as forges, looms, etc). Above all, one inherits the relationships along the supply chain and patronage, especially the tea masters themselves.
Japanese art, particularly the traditional forms, were hit particularly hard by bunmei kaika, the all-out Westernization movement of the early Meiji period, and went into a state of creative decline at the end of the 19th century. The new middle class that was moving into cities was hungry for modern life and Western-style art. At the same time, Westerners were mostly only showing interest in the exotic exported Oriental Japonisme.
A note about the Japanese term. I am using Jisshoku as did the Minpaku exhibition. I have also seen it written Jusshoku.
Elmar Schmeisser notes, “One of the very few exceptions may be the Rikyu hyakkaiki (100 lines / phrases, typically dated to 1590) on which [Daniel] Burkus has been working and sharing at http://chanoyu-to-wa.tumblr.com/. The fact that Varley and others write about these sources in ways that obscures their historically problematic nature is something that I have grappled with in my own scholarship on tea history.”
 Outside the Raku Museum there is a stone tablet with "rakuyaki iemoto raku kichizaemon taku" (楽焼家元 楽吉左衛門宅) written on it. Also, Japanese government websites and the recent English language publication by Raku note "楽焼十四代家元、楽吉左衛門" (14th generation iemoto). Yet Morgan Pitelka notes in a private comment: The term “oiemoto” is reserved for the leaders of the large, pyramid shaped arts organizations that have ranks of teachers and pupils, masters and practitioners. "Wakasosho" means young teacher, but in the ten craft families, usually the art is preserved within the lineage, not disseminated through teaching. It's a different organizational model." He notes that "Raku of course avoids [the pyramid shaped system] by monopolizing the practice one generation at a time. ...The only naming conventions in the Raku family that I'm aware of are the title 'Kichizaemon', which is held by the current head of the household, and the retirement name that ends with 'ryu" (e.g. Ichinyu, Sonyu, Sanyu, etc." More about this in his Handmade Culture: Raku Potters, Patrons and Tea Practitioners in Japan. It would be interesting to further explore when the Raku family began to use the term “oiemoto” for the generation “head”. Thanks to Lucinda Cowing for prompting further research.
 Mitsukoshi has been the leader in many modernization efforts to promote capitalism in Japan with a number of Japan's firsts: department store (1904), in-store restaurant (1907), escalator (1914), and fashion show (1927). The Osaka store was opened in 1691; it merged in 2008 with another company and the store closed 2014. "The decision to retreat from Osaka can be seen as Mitsukoshi's epilogue in its story of trying to regain its position as the top department store in Japan."
 Further research about Mitsukoshi and its gallery exhibitions of chadogu has pointed me to the Riseido Gallery which in 1918 - 1941 held "Oriental exhibitions every year at Mitsukoshi stores in Osaka and Tokyo." The Gallery was founded by Tamitsuchi Murakami, a green tea dealer in Hirano-macho, HIgashi-ku Osaka who operated under the trade name Shunchodo. The second generation owner, Tajijiro Murakami, married the daughter of the head clerk at the store and began an art trading company in that neighborhood.