Such a system is nearly impossible to be sustainable. Look at the EU, which can barely hold itself up together and is in a constant state of crisis ever since 2008. On top of that, the EU is fortunate that most of the member states have somewhat similar value and culture systems so how would you expect a worldwide government to manage hundreds of different cultures and value systems in one state?
Still as an individual you do have more freedom and opportunities than ever before, even the worst wage slaves cannot compare to working conditions some people had only 70 years ago in Western nations. It's much more difficult to control people who have access to information so perhaps I wouldn't be so pessimistic.