A good developer can create much more value than $150/hour (Google generates over $2 million per employee in revenue). A bad one can easily destroy that much value even faster (A developer at Knight Capital destroyed $440 million in 45 minutes with a deployment error and some bad configuration logic, instantly bankrupting the firm by reusing a flag variable).

$150/hour is a reasonable approximation of the cost of a professional senior software developer in the United States at this time.

Agentic AI means that anything you know to code can be coded very rapidly. Read that sentence carefully. If you know just what code needs to be created to solve an issue you want, the angels will grant you that code at the cost of a prompt or two. The trouble comes in that most people don't know what code needs to be created to solve their problem, for any but the most trivial problems. Who does know what code would be needed to solve complex problems? Currently that's only known by software developers, development managers and product managers, three job classifications that are going to be merging rapidly.

Claude created tests for not just the parser, but for the analysis and rewriting framework used to examine and manipulate the AST. It created invariants to check the functionality all of these, including several invariants I hadn't thought of. It realized that it wanted to test that parsing a Java class, then prettyprinting it, and parsing the output of the prettyprinter resulted in the same AST as simply parsing. Unfortunately, we hadn't yet written a prettyprinter for turning Java ASTs back into Java, so it wrote one. It did all of this in about fifteen minutes, with me adding no more to the process than occasionally typing "Excellent! Keep going!"

Decisions around how software should be designed, built, and tested are made not with respect to how to make the software the best it can be, but rather to optimize around that grinding $150/hour number.