While your arguments make sense, there are cases which that might not cover.
Here is a scenario: Today was a release day for our stack, we released multiple libraries and our router. The router is packaged as a snap, though that’s not our main medium of distribution just yet. We released our router to DockerHub, pypi and snap store, though the testing only took place for the docker container that are part of our CI.
So given the resources we have and the frequency by which we do releases, its a challenge for us to all that testing.
So maybe if build.snapcraft could provide some API through which we could find “which snap revision refers to which commit” then we could do some automation on our end and do the release through snapcraft release.