The capital holders in all industries would love expensive human labor to be replaced by cheap automated labor. If programming AI is created, no labor organization could save software engineers, just as it would be ridiculous to think horse and buggy drivers or telegraph operators could have stopped the march of progress.
The bigger issue is what has we've already started to witness: automation leads to accelerated accumulation of wealth and resources among those who already have the most capital. Historically, corporate profit and labor demand went up or down together. Now they're diverging: corporate profit grows while demand for labor shrinks. The spoils of corporate success goes to those who own the tools of automation, and others lose their job and income.
In any case, OpenAI's vision here is much bigger than making software developers obsolete: they want to study (or create) AI that can improve itself (i.e., a singularity scenario).