I'm starting to like more and more that you have a "devops" team that is responsible for the application in all environments. They deploy and monitor it but also expose that monitoring to others.

Then you have the platform teams that support them by managing the platforms they use, the monitoring solutions etc. and work as much as possible so the devops teams can be self service.

I have no experience with it though but I feel that having all knowledge in all devops teams does not scale to any sufficiently complicated environment and the idea of the dev team not being responsible for deploying to production sucks.