Pretty cool read, and the breakdown of how to bring about that collaboration is a good read.
Back in the day you would have one team writing code, and another team managing the infrastructure + deployment.
The problem with this team breakdown is the lack of ownership and the delay in feedback. Devs aren't incentivised to make the software work well, and SREs aren't incentivised to deploy new versions of software. DevOps should be a strategy to resolve these dysfunctions.
Unfortunately, most companies just renamed their infra roles to devops roles, and called it a day. They weren't resolving their core dysfunctions in their team composition.