> The jobs could themselves become more desirable with machines automating the boring and dangerous parts

Or, as Cory Doctorow argues, the machines could become tools to extract "efficiency" by helping the employer make their workers lives miserable. An example of this is Amazon and the way it treats its drivers and warehouse workers.

That depends on the social contract we collectively decide (in a democracy at least). Many possibilities will emerge and people need to be aware and adapt much faster than most times in history.