The problem is when people ignore it and just let it continue to chirp for days on end. As someone who lives in a building with many neighboring units, I hear this chirp often. Luckily it is usually only noticeable when you are nearby, but if you live next door or above or below, chances are you will be able to hear it from your own unit.
I don't understand how people put up with that when their smoke detector is chirping for days. Just change the battery, or at least take the battery out until you can replace it so it stops beeping. Sometimes this may occur in a vacant unit which is just as annoying because there is no one even there to change the battery.
I'm trying to think if there is any other better or less annoying way a smoke detector could notify you that it is low on battery. They could probably go with visual cue like a light, but it might not be noticed, so the chirp is still probably the best option. Looks like it is here to stay, so please if your smoke detector is chirping, change the battery or replace it asap!