Why would informing people about the importance of testing make you look like an asshole? You could do it in a polite and helpful way, instead of being an asshole about it.
> the article in question called it an asshole thing to do [publicly calling out and blaming others]
It's all about how it's done. In the case described above, an explanation of what happened, why it happened, how to avoid it in the future, and perhaps a little humor would be positively received by everyone involved.
On the other hand, someone could very well have the exact same situation and make it into a-hole incident by shaming the interns and making them reconsider even being there.
Automation takes this and a whole class of problems out of the interpersonal domain. Failed tests make the build fail. Who ever breaks the build buy donuts for the team. Easy, solved and no personal issues. Include a linter in the build, incorrect formatting fails the build. The team decided on the standard format (tabs vs spaces, 4/2 spaces, brace same line or next line etc). More donuts. No arguments because linting rules were decided by the team. New members adapt.
>Publicly calling out and blaming others