A handful of SDN-listed pools still have an “operator” authorization. Of those, two belong to really old, now-unused versions of Tornado Cash. The remaining pools either have more recent, immutable versions, or had been employed so small that they were being very likely forgotten over the Could 2020 remaining update. https://cafelevictoria.com/why-tornado-cash-is-the-go-to-privacy-protocol-for-copyright-users/