Sure, let me get out my crystal ball... Honestly, we cannot know. That said though, if markets continue to be free, and the competition for buying labor continues to grow, then yes, labor unions will not have a reason to exist if their aim to protect workers. Even in the United States, the increases in worker quality of life and workplace safety has not come from government agencies or union demands, but from workers preferring to work in safer environments that better compensate them.