> When e.g. receptionists start tossing together their own productivity apps in a few minutes, then we will have entered into the next phase of the economy.
This isn't a matter of tooling through. Receptionists won't start making their own productivity apps because most people do not default to "I will make my own thing to solve this".
Maybe some receptionists will, but most won't, just like most people won't patch their own drywall even though the tools are available in every hardware store
Now imagine somebody could just describe some damage to their drywall in a text message to their computer, and it'd be magically patched away. Suffice to say, nobody would be calling in for drywall repair.
Before computers, there were computers. [1] It's obvious in hindsight, but all of these complex numerical calculations we take for granted were often not done by the same people applying them in various ways. They'd hire computers instead, which were human calculators whose job it was to do the math.
The reason these jobs no longer exist is because calculators/computers not only solved these tasks, but completely trivialized the process to do so. We're entering into a world where many cognitive tasks, including software development, are going to be trivialized in a similar fashion - describe the problem, get an answer.
And I think this is going to do similar things to what calculators and computers did (or widespread literacy for a more historical example). The ability to e.g. write a program will no longer be a valuable skill in and of itself, but simply an expectation of anybody in any role where it might be desirable to do so.
[1] - https://en.wikipedia.org/wiki/Computer_(occupation)