The fact that the developer was prosecuted under Chinese law is important to an audience of developers who want to know what precedent it sets for their own work.

Sharing private information public either intentional or unintentional that leak customer data and weaken the software security is illegal in any country as far as I know.

He claims it was a mistake. Checking in private keys is a fairly common mistake and seems analogous here. https://m.slashdot.org/story/181081