Knowing something is wonky and knowing how to fix something wonky effectively without pissing anyone are completely different level of tasks though.

Knowing things is bad only requires knowledge of the product itself. But fixing it requires understanding of the whole infrastructure and members around the project.

An outsider can't do it. And the insider don't necessarily think the project is bad from his perspective. You would have to argue with him to convince him the project is bad. Which really don't bring any value to the outsider themselves. And it can even be harmful.