Wilfred M. McClay in The Hedgehog Review:
When we find words being used in a novel way, our countenances tend to stiffen. What’s going on here? Is this a euphemism? Is there a hidden agenda here?
But there are times when the older language seems inadequate, and in fact may mislead us into thinking that the world has not changed. New signifiers may sometimes be necessary, in order to describe new things.
Such is unquestionably the case of the new/old word influencer. At first glance, it looks harmless and insignificant, a lazy and imprecise way of designating someone as influential. But the word’s use as a noun is the key to what is different and new about it. And much as I dislike the word, and dislike the phenomenon it describes, necessity seems to have dictated that such a word be created.
More here.