You've missed the part of the 1st quote about multi-stage builds and other methods which avoid exactly the problem mentioned in the 2nd quote: the resulting image would consist of it's base image and artifacts from previous stages while being run in the same build step of a pipeline.
Docker allows you to pull a cache from anywhere with a --cache-from command. See dockumentation here: https://docs.docker.com/engine/reference/commandline/build/#specifying-external-cache-sources
The easiest approach is to build your images with the --build-arg BUILDKIT_INLINE_CACHE=1 flag which stores the metadata needed to build from cache. You can store ...
If you really want to, you can use
or even better
there is the log of the last successful build, the others are: