Your build tools are great, but no one wants to learn them
I’ve never worked somewhere that had a completely off-the-shelf CI/CD system. In some cases the systems are just minor tweaks or wrapper scripts over common tools (usually Jenkins). In extreme cases it’s completely from scratch tooling that has syntax and behaviors I’ve never encountered before.
They’re usually hyper optimized for a majority of internal applications or specific languages, but they completely fail at being useful for the last 10-20% of internal applications. In the name of developer productivity we try to be special and I’m not sure if that says more about the state of general purpose CI/CD systems or developers desire to over optimize.
I don’t like them and prefer working around issues with common tools than streamlining with custom solutions.