Not really though. Equating docker with OCI is kind of like saying gmail is the same thing as SMTP. Gmail works with SMTP to send messages, and docker works within the confines of OCI to create images.
While Docker is mostly OCI compatible these days (I say mostly as they extend their tools beyond it, making it hard to replicate the build without using docker itself. Not in-and-of itself a bad thing, but still annoying for portability), it shouldn't be confused with the OCI itself, which is there to help safeguard against companies like Docker going off and doing incompatible things.
While Docker is mostly OCI compatible these days (I say mostly as they extend their tools beyond it, making it hard to replicate the build without using docker itself. Not in-and-of itself a bad thing, but still annoying for portability), it shouldn't be confused with the OCI itself, which is there to help safeguard against companies like Docker going off and doing incompatible things.