I am starting to have a hard time who is responsible for what. I no longer know what's the relationship between companies/products like Anthropic, Cursor, SpaceXAI, Copilot, etc.

Nobody seems to be taking responsibility yet for what exactly was compromised, how, and what steps are being taken to prevent it.

It was 100% an "official" Anthropic extension. They say their systems were not compromised which, if true, suggests a bug or credential leak on the Cursor side. Cursor conspicuously left these details out of their public notice.