Decline of Computers as a General Purpose Technology

Contributed article, excerpt below in the March 2021 CACM.

My first reaction was No!  But some very good points made ... '

The Decline of Computers as a General Purpose Technology   By Neil C. Thompson, Svenja Spanuth

Communications of the ACM, March 2021, Vol. 64 No. 3, Pages 64-72  10.1145/3430936

Perhaps in no other technology has there been so many decades of large year-over-year improvements as in computing. It is estimated that a third of all productivity increases in the U.S. since 1974 have come from information technology,a,4 making it one of the largest contributors to national prosperity.

Key Insights  ...  

- Moore's Law was driven by technical achievements and a "general purpose technology" (GPT) economic cycle where market growth and investments in technical progress reinforced each other.  These created strong economic incentives for users to standardize to fast-improving CPUs, rather than designing their own specialized processors.

- Today, the GPT cycle is unwinding, resulting in less market growth and slower technical progress. 

- As CPU improvement slows, economic incentives will push users toward specialized processors, which threatens to fragment computing. In such a computing landscape, some users willbe in the 'fast lane,' benefit ing from customized hardware, and others will be left in the 'slow lane,' stuck on CPUs whose progress fades. ... 

The rise of computers is due to technical successes, but also to the economics forces that financed them. Bresnahan and Trajtenberg3 coined the term general purpose technology (GPT) for products, like computers, that have broad technical applicability and where product improvement and market growth could fuel each other for many decades. But, they also predicted that GPTs could run into challenges at the end of their life cycle: as progress slows, other technologies can displace the GPT in particular niches and undermine this economically reinforcing cycle. We are observing such a transition today as improvements in central processing units (CPUs) slow, and so applications move to specialized processors, for example, graphics processing units (GPUs), which can do fewer things than traditional universal processors, but perform those functions better. Many high profile applications are already following this trend, including deep learning (a form of machine learning) and Bitcoin mining. ... 

With this background, we can now be more precise about our thesis: "The Decline of Computers as a General Purpose Technology." We do not mean that computers, taken together, will lose technical abilities and thus 'forget' how to do some calculations. We do mean that the economic cycle that has led to the usage of a common computing platform, underpinned by rapidly improving universal processors, is giving way to a fragmentary cycle, where economics push users toward divergent computing platforms driven by special purpose processors.

This fragmentation means that parts of computing will progress at different rates. This will be fine for applications that move in the 'fast lane,' where improvements continue to be rapid, but bad for applications that no longer get to benefit from field-leaders pushing computing forward, and are thus consigned to a 'slow lane' of computing improvements. This transition may also slow the overall pace of computer improvement, jeopardizing this important source of economic prosperity.    ...."