When did capturing the reader's attention become "manipulative tripe?" The goal of any piece of writing is to persuade and convince. Opening with an engaging anecdote is a time-tested tool for bringing readers into a piece. Writers have been doing this for centuries. Would you rather the author reduce the article to a list of bullet points?
So it seems when writing in English for a French audience that using more often "an" would lend "an helping hand" to understanding (by supporting the internal voice)
Northern UK here. "An' istoric" is very common in informal speech, even in the south but more so in these parts, but I wouldn't expect to see it written that way.