Back in the day that the author initially started working, the nature of the relationship was probably much more balanced: the employee got a decent wage, was trusted to fulfil their duties with reasonable concessions and freedom (sometimes possibly doing overtime if necessary, but also being able to leave early on days when they had to take care of their kid), and they probably had much better implicit labor protections: in the event of economic downturns, the company was much more accommodating and tried its best to take care of the employee. In other words, the employer was trusted and the employee was trusted to "take care of each other". The job was "for life", after all.
Fast forward to these days: companies have stripped away a lot of the care they took for employees; in the event of economic issues, big corps will fire people basically at random. Most employees are monitored to the minute, and leeway from the employer is unheard of in most situations. All of this "taking care of your employees when things go awry" is expensive (like insurance) and employers have tightened their belts.
It's not surprising then that the employer also starts looking for ways of not doing more than they are contractually obliged to do.
It is mostly about the erosion of trust both ways.