Comment by hunter2_

> People will complain that this is "wrong"

I think most such "people" (those who oppose the use of singular they) would limit their opposition to a particular subset of usage, which is pointed out in the Wikipedia article you linked to as follows:

> In the early 21st century, use of singular they with known individuals emerged

I doubt they'd be opposed to the centuries-old usage being proposed in this thread, which Wikipedia mentions like so:

> to refer to an unknown person

But who knows!