I'd phrase it slightly differently. We can and should fix things in response to CI failures. The problem is more so the cost/value trade off for developers.

I'd phrase it slightly differently. We can and should fix things in response to CI failures. The problem is more so the cost/value trade off for developers. The lower the perceived value is, the more good will that will be lost with developers for having to do another iteration to fix them. Integrating these into the developers workflow as early as possible, like rustfmt or gofmt, lowers the cost and developers are less likely to have a problem with it. At this point, the main value of having something in CI is either for the reviewers to give them a sense of things, like coverage or to help enforce people are using those tools, which means it should ail CI.