[caseysoftware]

This was the common argument 10 years ago as open source CMSes - primarily WordPress and Drupal - started becoming more common. That eventually web developers would be entirely replaced by people who just configure plugins/modules.

As we've seen, software development has stagnated and almost gone away in the ten years since.

[makomk]

Open source CMSes increase efficiency - by reducing the amount of work required to set up a website, they mean that the time and money saved can potentially be used for more productive purposes. Working for free doesn't do that; it involves the same amount of work and time, just for free.