Why would SREs be responsible for build and test infra? I don't see how that fits the mission, unless the mission is redefined as "things developers perceive as being beneath them."
It can be the role of SREs to build and provide the infrastructure improving the reliability of rollouts, allowing the rest of the company to build reliable products without compromising the velocity.
Well yah, that’s exactly it. Ego thing. Things will roll down hill until it hits someone who can actually fathom a coherent story for the org.
SRE provide the gitlab/jenkins? Sounds normal to me.
That's exactly it. For some reason, developers really want to just write code, even though it's for a web service and that web service doesn't exist in a perfect vacuum. (Yes, I do ops, and yes, I'm bitter and jaded.)