I argue emojois make it easier to understand. Whether conveying sarcasm, frustration, joy or anger. It's much easier to infer the tone of a message using emojis.
I'd agree that for emotional context, it can be useful. But I don't think the way they are used there is easy to understand. I mean what's the meaning of the heart regarding CI or the pen for bugs? Is that indicative of a categorie of commit (CI, bug-fix...) or just to decorate the message?
Also another issue is that emojis are not as easily indexable/searchable.
Well, in this comment thread we have "it's not nice to see them work [in this case]" and "I'm not sure how I feel about emojis working [in this case]."
So, no, I don't think the issue is that they don't work in this case.
HN definitely does have a knee-jerk hate for them, and if you spend enough time here you'll see that a lot of it really is just "gah, young people." It's the new hate on txt-speak.
Even if they manage to convey a meaning, like the other poster said, that meaning is emotional instead of factual.
Why would anyone ever wish to express emotions in a commit message, or even in a business communications tool like Slack, is beyond my comprehension.
For personal communication they can serve a purpose, but that's not the topic here.