While I believe that to a certain degree it is correct that automation doesn't necessarily result in less human work, the view taken and example in the article is fundamentally flawed.
In the case of the shoe factory given the example of a machine, operated by a human, being replaced with a more efficient machine not reducing the human work hours because the company simply produces more shoes has never been the concern about automation.
The idea that automation allows you to either increase efficiency or production volume or both is of course the driving force behind automation but the concern about job losses doesn't come from replacing one machine with a more efficient version of the same, it comes from the possibility of the automation removing the need for a particular skill set that a certain group of employees have.
If your skill set is no longer needed in your profession because the job has been automated, there may well still be human work to be done in the form operating and monitoring the new automated equipment but this is not part of your skill set and you are now out of a job.
To say that "there is no reason to fear (or hope) that automation will put people out of work permanently" may well be true on the grander scale, as a percentage of the population and over time certainly the unemployment will be temporary.
But what of the workers who are made unemployed by automation who don't have another skill set to gain employment with, and are of such an age where once they have retrained to do something else their prospects of gaining new employment are exceedingly low.
HGV or Taxi drivers are a good example of this, if we reach a point where all driving work of this nature becomes automated, what does a say 55-65 year old HGV driver with no other skills or work experience beyond driving HGVs and no qualifications besides a HGV licence do when he is made redundant? Where does his income come from when he can't find work because the only work he was qualified for has been automated, and he is still a number of years from being able to retire and draw pension.
Certainly I would agree that in the long term, on a large societal scale, there is no reason to fear automation putting people out of work. Since as certain areas of work are eliminated by automation, the education system will adjust to direct people toward other forms of work and training and new young employees will be seeking different kinds of work.
But to say "The Automation Argument simply misunderstands how our economy works" is not true. The Automation Argument does understand how our economy works, but our economy doesn't give a flying fuck about the individual worker it only takes account of the population at large scale.