I think the main thing about agile is a plan-do-study-act cycle than can be adapted to anything even project management. The trick is not to think I can just adopt a process and will then be agile. It always has to be adapted to context and what works for you.

As to CI/CD pipelines: I think a centralised devops team that blocks everyone is as much an anti pattern as a wild-west approach where 3 teams operate 4 different CI/CD tech stacks. There is much to be said about building a platform (when the size of the operation is big enough to warrant it) and using golden paths or paved roads.