Bitcoin wouldn't work without it - sure, it's a building block, but the core innovation behind Bitcoin is not asymmetric crypto. The parent comment was implying that using asymmetric crypto in finance would solve problems with security and fraud, when in truth, asymmetric crypto has already been in use since well before Bitcoin came along, and is an important technology but has not magically solved all our security problems. There are multiple separate things being conflated here in incorrect ways.
It does, Bitcoin wouldn't work without it, the whole thing relies on cryptographic signatures.
> The "double spend" problem refers to a problem in distributed systems, not applied security.
Is it not both? It's a security issue present in distributed systems.