I was talking to someone a week ago, she was saying that she's sympathetic but just can't get used to a singular "they".
I said "yes, you can. You already use it". A coffee table was between us, so this is the example that jumped to mind: "Can you not imagine walking in here, seeing a problem on this table, and saying, 'Who left this ring? Someone just comes in here with their drink, and they don't use a coaster?"
Her mouth kinda hung open after that.