> They discuss the changes as the team are doing them (software design and architecture)

I find the format of PRs to be better suited to discussion than slack/teams messages. Key developers need to actively sign off, code suggestions are much easier, and the CICD makes sure we're not wasting time discussing code that's not compliant with obvious standards.

Obviously some level of agreement is needed before creating a ticket at all, but implementation details around say creating a terraform module to share functionality between teams do need to be discussed somewhere - and it can be difficult for any individual dev to have all the low level context.