They can see where I am, down to my address, at any given time.
Why not?
The very real upside is that they casually see me while looking at Google Maps and strike up a conversation or invite me somewhere, something that's happened many times.
The article talks about private and public life... but people will go to all the effort to post the very same things their location reveals on social media. Might as well make it real time.
If you're sharing location data with people who would use it to harass you, that seems like a selection issue, not a systemic issue.
Location data is hardly private. Everyone should share theirs with as many interesting people as possible. If only I had done so back in school.