Forges are great for OpenSource software but for closed source/commercial groups in an agentic world I think (ultimately) all you'll need is a git remote with:

  - access control (gitolite or similar) + key management (small webapp or api)
  - branch protections, there's no prior art that I am aware of but hooks can be used for this)
  - CI can be done by hooks as well, probably dispatching into a queue.

You don't really need PRs, agents can review the branch, humans review evidence. You probably don't need Wiki's or GH Pages or Discussions.

You might use tickets, but they make cross repo planning and tracking difficult.

Hell, you probably don't need Confluence or Jira since docs and tickets should be in the repo itself (self contained state for agents). I am working on tooling for this... (an experiment!)