From a GitHub product owner POV, if the architecture is not to be changed, what is the solution?

A big ugly warning in the UI?

Or, push back on the architecture?

Or, is threatening a big ugly warning in the UI actually pushing back on the architecture?

Many projects kind of take a different approach where for pull requests CI is not run until approvals from maintainers are given even for very simple jobs to avoid untrusted code running in ci.