Clearly, most regulators haven't realized how bitcoin can indeed became a threat to financial stability.

A bitcoin news site published this :
Powerful U.S. Regulator Sees Bitcoin as a Possible "Threat" to Financial Stability - CCN: Financial Bitcoin & Cryptocurrency News

https://www.cryptocoinsnews.com/us-regulator-bitcoin-financial-stability/

The study by the regulator can be read here:

https://www.treasury.gov/initiatives/fsoc/studies-reports/Documents/FSOC 2016 Annual Report.pdf

However, its comments on bitcoin are very limited (see p. 127) and clearly doesn't address the main issues. Probably, because, currently, they are no issues.