2. ditto. The 'best case' for a labor union is that their members are highly skilled and hard to replace, with lots of alternative employers.
3. The article clearly states that Agile is not implemented in order to protect developers, but the net effect is the same. Agile team/management relationships cannot be adversarial because Agile.
The point the article makes is that UCD separates the design of the system (the bit that needs management and user contact) from the implementation, which then allows the implementation (as wildgift points out) to be considered a cost and Taylorised (squeezed) into 'efficient' permanent crunch time.