Comment by solatic

OP's argument hinges too much on thinking that GitLab pipelines etc. only do CI.

The purpose of Continuous Integration is to produce the One Canonical Latest Build for a given system. Well... no surprise that there's a ton of overlap between these systems and Bazel etc. "build systems".

But GitLab pipelines etc. are also Continuous Deployment systems. You don't always need fancy ArgoCD pull-based deployments or, their precursor, Chef/Puppet were also pull-based deployments for VMs. You can just have GitLab run a deployment script that calls kubectl apply, or Capistrano, or scp and ssh systemctl restart, or whatever deploys the software for you. That's not something that makes sense as part of your build system.