This is a post about smartphones, but it seems to be that Horace Dediu’s framing of modular vs interdependent systems for different kinds of situations has a broad applicability:
Interdependent systems often lead to higher performance than modular systems because the system is optimized. Engineers can iterate more rapidly to squeeze the maximum performance from sub-systems by connecting them in ways that makes the best complete solution. In contrast, modular systems often lead to lower costs because there are a greater number of suppliers, since interfaces are standardized and pieces can be swapped in and out.
Interdependency is often required to raise the performance of a new solution. In contrast, modularity is required to lower the cost of an overserving solution.
Continued interdependency often drives the performance of that solution beyond that which the target market is willing to pay for. The target market then frequently turns to modular solutions which, at that point, often offer good enough performance along with modularity-driven advantages such as lower cost, convenience, or other benefits.
This puts me in the mind of higher education in the United States. The college experience is a very full-service, highly integrated kind of thing. It’s part school, part sleepaway camp, part job-placement service. And it’s ungodly expensive. It’s possible that a this point in our historical development we could use more modularity. That might allow us to do a better job of holding down costs in some aspects of what needs to be done, and also allow many students to avoid overpurchasing services they don’t especially want or need.