You raise a key point regarding debasement, which was certainly a driving force. True success, however, might also be measured by a system's resilience and its adherence to foundational principles over time.

No. Measuring against fiat is a mistake. Bitcoin's success or failure is in giving people the opportunity to *opt out of fiat* and transact directly with each other. Looking to fiat price to measure purchasing power is A metric, but it's not THE metric.