The article says: [Agile] does this by limiting the number of working hours, demanding autonomy and self-management, rejecting the arbitrary dominating power of the boss, preventing their jobs from being shipped overseas, and ensuring that software engineers are involved in their workplace as decision makers.
1) "limited working hours" - the essay quotes Beck on prohibiting more than 40 hours of work per week, and says of crunch time that "Agile methodologies rightly reject this as inhumane and unsustainable." However, waterfall methodology also rejects this as unsustainable. The reference I have is for Jones 1991, which says that Voluntary Overtime is effective up to about 44 hours per week, and beyond that effectiveness is likely to get worse.
So, you're doing agile. Your boss wants mandatory overtime, with 50 hour weeks for the next 3 months, in order to beat some deadline promised to the board. In a union, you talk with your union rep (who may have been involved in your contract), and present a united front against the arbitrary and fundamentally poor decision.
In an agile shop you ... point to a book which says that 40 hours is enough? Then when your boss points out that the industry average is 48-50 hours, you say ... ? And you are effective because ... ?
2) "rejecting the arbitrary dominating power of the boss"
I didn't see where that was really developed, other than some specifically project related decisions. Can agile prevent the boss from firing an employee any more than waterfall can do so? Can agile fight towards getting the salary increase you were promised for working 60 hour weeks, but never got? Not that I'm aware of.
While unionization is supposed to offer that sort of protection, agile only rejects certain limited forms of boss power.
3) "preventing their jobs from being shipped overseas"
The point here is that outsourcing can't happen with a methodology which requires co-location with the customer. "The forth and fifth principles mandate co-location of the engineering team and daily interaction with business people" where from the Agile Manifesto: "4) The most efficient and effective method of conveying information to and within a development team is face-to-face conversation. 5) Business people and developers must work together daily throughout the project."
Except that those principles don't require on-site work, only say that on-site is the "most efficient and effective method." There are any number of web page which talk about "distributed agile", for example.
For example, here's a page talking about how to build an agile off-shore http://www.agilebuddha.com/agile/distributed-agile10-good-pr... . It argues that frequent travel for in-person contacts is essential, and still requires daily meetings, only through videoconferences and other means.
While agile would say this not as effective, it doesn't reject this outright, so it cannot be anti-offshoring.