Dismissing the idea solely because "dumb governments" won't endorse it is a bit shortsighted.  Global financial reform requires a shift in mindsets, not just at the governmental level, but also among the "elites" who control major financial institutions.

Is mass adoption a prerequisite for Bitcoin's success as legal tender?  Perhaps not.  El Salvador's experiment, while still in its early stages, demonstrates the potential for smaller economies to embrace Bitcoin first.  Imagine a domino effect, with other nations following suit as the kinks are ironed out.

The transaction speed and cost issues you mentioned are valid concerns.  Bitcoin's current infrastructure simply might not be scalable enough for everyday transactions in a large economy.  However, advancements like the Lightning Network are being developed to address these limitations.  Imagine a highway expansion project –  a necessary step to accommodate increased traffic.