In general I agree, but in your specific example (assuming that there's a universal coding convention that everyone is expected to follow), I think your "Bad" is better than your "Good". If something is obviously wrong, call it out, simply and factually. Chances are it was a simple oversight, and "Why did you decide to go against our naming conventions?" sounds passive-aggressive.

I find questions most useful when the issue really is a matter of opinion, and they're just as likely right as you. For example, "why did you decide to key this webpage's data by content hash instead of by URL?" This is a sincere question - there may be arguments for both approaches, and the point in asking is to tease out those arguments and figure out what actually is the truth. It's an acknowledgement that you might be wrong, and not an attempt to paper over the certainty that you're right with diplomatic phrasing.