Well.. GO is designed for both CI and CD. You can trigger Go builds which are linked to Github/Git Commits.. But Travis does have some advantages in few areas, like ability to check pull requests on Github.
You don't own the Travis VMs, whereas Go will run on your own infrastructure. Travis provides you free infrastructure (recreated on each build) on which your builds will run, but you will still need a local environments where your build artefacts are created, and maintained, for setting up deployments in stages.
For instance using Go, you can create pipelines which
Build -> Deploy to QA --> Run Functional Tests --> Deploy to Demo environments --> Create publishable artefacts (etc)