That's a false argument. To many people that's a good self supporting job. No one should criticize how someone makes an honest living.
The bigger argument is when you lose the sewing machine job you lose the plant manager's job, the fabric salesman's job, the engineers who design the next generation computer controlled sewing machines right on up the ladder.
As for the rest: our realmedian incomes continue to rise (although, admittedly, there has been a leveling off for the last three years). And also our standard of living has never been better.
Some people are harmed to be sure. Most move on to something better while receiving government aid in the interim. Certainly if you examine the process over just one generation, life does get better.
By the way, when was the last time you read about someone in America starving?
Shall I keep going with my false arguments?