1. Description of phenomenon
Tim Urban wrote about the movement towards the non-overlapping-ness of output in his Wait But Why (WBW) Neuralink post (search for "Language is the difference between").
His image gives a good graphical representation of the phenomenon:
The gist is that human language allows the transmission of an individual’s lifetime learnings to other individuals or to a knowledge commons (cultural memory as I understand it). If there is no transmission of learnings, culture does not progress, in that each individual starts in the same “place”, in terms of know-how, as their ancestors. If there is significant transmission, each successive generation starts with more tools at their disposal (mental, physical, or otherwise).
I am generalizing Urban’s idea to the creation and transmission of software systems.
2. Description of possible enabler-of and catalyst-for said phenomenon in networked computer software systems
cdixon writes here about how blockchains and cryptocurrency systems can create stable information infrastructure on which developers can build applications:
... unlike a traditional computer, a blockchain computer can offer strong trust guarantees, rooted in the mathematical and game-theoretic properties of the system. A user or developer can trust that a piece of code running on a blockchain computer will continue to behave as designed, even if individual participants in the network change their motivations or try to subvert the system. This means that the control of a blockchain computer can be placed in the hands of a community.
Making reference to the above WBW image - as I see it, if a developer builds an application on top of a closed system, they are building a house on an unreliable foundation which could give way at any moment. Their "blue bar" (from the image) pokes upwards - incremental progress which yields increased productive output for them and users of their system. But if/when Google changes the rules and destroys their foundation, their blue bar will drop down and the "overlap" will increase.
In order for the productive output of humanity to increase maximally, we need maximal non-overlapping-ness of blue bars.
As companies like Google, Twitter, and Facebook built software and services that surpassed the capabilities of open protocols, users migrated to these more sophisticated platforms.
If systems with open governance can be built which can surpass the level of sophistication & capability of the aforementioned proprietary system, then we can collectively cement non-overlapping-ness of technological contributions.
This both increases our collective human productive output, and (importantly!) increases the individual's incentive to attempt to productize an "evenings and weekends project". It becomes much more likely that their project's foundation will stand the test of time and not crumble from beneath them. For small developers without the engineering manpower to constantly fortify and rebuild their foundations, a collapse can be fatal.
4. Potential for exponential growth
It's possible that a network whose members can consistently create non-overlapping productive output will have exponential growth of total system productive output.
If members can build on each other's productive contributions in a way which only progresses and never (or rarely) regresses, it seems to me that each individual's "blue bar height" could increase, since the tools which are available to them are ever-increasing in power.
Exponential growth ... occurs when the instantaneous rate of change (that is, the derivative) of a quantity with respect to time is proportional to the quantity itself.
If the productivity of each member increases as a function of total system productivity P, that means that dP/dt increases as a function of P. This matches the definition of exponential growth.