Personally, I prefer something written in a relaxed style rather than a formal-voice only in most cases, especially for blog posts.
Formal only generally comes across, to me, as cold and distant. Great for a persuasive essay or other mediums where you want to remove the topic from the author, not so great for communicating with your audience and wanting to come across as sincere.
If anything, a strict formal-voice only blog post would come across, to me, as contrived.
I'm not advocating for formal over relaxed. I find blog posts work best in a relaxed style from the first person singular. This sort of apology should come from an individual at the top, and make reference to the whole team. You're probably right about personal differences though.
