I believe it's very difficult for Bitcoin to drive the global economy, let alone completely replace fiat currencies, due to regulatory factors, price volatility, and uneven mass adoption. Bitcoin's highly volatile price makes it less than ideal as a daily medium of exchange or a stable store of value. When prices can fluctuate dramatically in a short period of time, people tend to hesitate to use it for routine transactions.

Additionally, fiat currencies are backed by governments and established financial systems, so a full transition to Bitcoin would require major changes in the global economic infrastructure. Most likely, Bitcoin will continue to develop as a new asset class that complements the traditional financial system, rather than completely replacing it in the near future.