The Kokoro docs-presubmit job will be removed in cl/667593059

So is the docs-presubmit check not doing anything useful? Will the docs still update as expected even if the test fails?

So is the docs-presubmit check not doing anything useful?

Correct. The publish docs job runs /.kokoro/publish-docs.sh here where as the current docs presubmit job runs /.kokoro/build.sh here. When we call build.sh in the docs-presubmit job we're just running the docs/docfx nox sessions which is already done using Github Actions(See docfx presubmit). We're not testing the publish-docs.sh script or the Dockerfile here.

Will the docs still update as expected even if the test fails?

Yes, the docs job can succeed even thought the presubmit fails because they are 2 different scripts as noted above. In addition, the docker file is built on the fly. I've filed a bug to remove this step to improve the success of the jobs pipeline: googleapis/synthtool#2007

Wait for cl/667593059