The treatment this woman received is only marginally worse than what most salarymen have to put up with.
While they have no curfew, they're usually working until 10pm anyway. To prevent salarymen trying to leave there are many tactics available. They pressured to do unpaid overtime until they don't have time to have a life outside work, so they come in to work to find something to do on weekends. Nor do they have time have time to go to interviews to change jobs, because their company won't let them take paid leave unless they have finished all their work (which is never, because they'll always find something for them). Even should they dare try to quit they are bullied and cajoled into working just "a little bit longer" because they haven't finished their project or whatever excuse is available - in order to delay the inevitable.
But hey, "shigoto daiichi" because the boss is screwing you all over and telling you to "take it for the team". And "ganbattekudasai" is a freaking joke because you could take a half-dead zombie and a genius university graduate, put them in whatever Japanese company you like and they'll both be paid the same wage because of their age anyway. Ganbatte my ass.
(rant over)