I pretty much agree. While any semblance of a "horizontal" dynamic in Japanese software development was perhaps realized in embedded systems around 40 years ago (e.g., rice cookers with fuzzy logic, or, in a different sense of _lateral_, Gunpei Yokoi’s famous philosophy of "Lateral Thinking with Withered Technology"), software has traditionally been undervalued in Japan. This historical neglect has ultimately contributed to the decline of our consumer electronics industry. (Though personally, I still don’t see why a toaster or a fridge needs to be connected to the internet.)

IMO, the tight-knit division of labor between Toyota and its subcontractors is a slightly different story from the broad diversification within a single corporation. While the latter was historically bolstered by strong industry-academia ties (often driven by university cliques), we rarely see this kind of broad diversification happening in recent years. That said, Japan's traditional "membership-based" employment system, combined with a cultural reluctance to shut down unprofitable business units, is likely what has allowed this diversification to persist for so long.

In any case, Japanese companies are currently struggling with the friction between their traditional corporate culture and the superficial adoption of Western concepts like DX, Agile, meritocracy, job-based employment, and a startup-centric mindset. I suspect Korea might be facing similar structural clashes, though perhaps you are adapting at a much faster pace.