Bitcoin is never going to become the world's currency. Even if that was possible, governments wouldn't allow it for a variety of reasons that have been previously discussed at the forum. I'm generally against such bold statements, especially those that concern the extremely distant future, like the OP is mentioning, the years 2048 and 2109 respectively. Even the so-called prediction is so far off, with a range of over 50 years inbetween. Bitcoin isn't capable of solving worldwide issues, it doesn't grow on trees, you cannot create it from scratch, unless you're mining it, which requires expensive equipment and expertise that the average person doesn't have. Thus, it's unlikely, not to mention impossible, that an asset like Bitcoin can solve worldwide issues such as poverty, hunger, or the financial crisis.
Without getting into the philosophical debate about Bitcoin having inherent value or not, Bitcoin adoption was never supposed to be government endorsed nor was it ever suppose to solve the world's problems. Poverty, hunger, financial crises, etc. are all caused by government mismanagement, debatably. Currency isn't meant to solve these issues directly, it's medium for exchange.
A country with access to open markets and education can spur up economic activity from nothing. Given that some degree of education can be obtained online, the portion that's missing is access to open markets. Bitcoin provides aide in that regard -- it allows for easy P2P commerce.
