I think it is naive to think that a bad actor who intends you harm will be stopped or even slowed down by the fact that there isn't a log of every location you've visited.

I think that that is a ridiculous statement. Of course giving a bad actor more opportunity to act badly increases the risk.

A threat to your safety or your freedom needs to be dealt with directly by eliminating it, not hiding from it. If you're envisioning a bad actor with the resources to compile and analyze a comprehensive log of your location, the simple fact that you use service A instead of service B is not going to do a thing to stop them if they're out to get you. You have far bigger problems on your hands.

What about a potential threat? You are not allowed to "eliminate" those. Maybe just don't give that potential threat more power.

"Potential threat" is an unbounded set. If you're going to guard against every potential threat you will not be able to spend your time doing anything else.

I asked because I was curious about what sorts of unique threats are presented by, for example, a database of location data. So far I haven't seen any that aren't already present via far simpler means.

It does not take an unbounded amount of time to simply not give information to an unbounded set. In fact that takes no time at all.

The point is not that the world will end if we give away our location data, only that doing so has a non-zero cost.

If you have a cell phone, it is constantly pinging nearby cell towers. If it has wifi, it is pinging nearby wireless networks. That information is out there, waiting to be collected. If you want to go without the benefits of a cell phone to avoid whatever threat is posed by somebody knowing where you were at some point in time, go for it. I think it's a waste of time.

I think there has been some confusion here. When I said that "The point is not that the world will end if we give away our location data, only that doing so has a non-zero cost" what I meant was that the point is not that the world will end if we give away our location data, only that doing so has a non-zero cost.

Cell phones are like cars, they are very useful but also have their downsides (cell phones reduce privacy, cars kill people). I have a cell phone and a car because I made a decision that the cost was worth the benefit. I did not need to delude myself into thinking there was no cost nor did I need to pretend that the cost was inevitable.

The threat of a comprehensive database of everywhere I've been is extremely minimal. There's not much someone can do with that that they couldn't do without it. If some whackjob want to wait for me to turn the corner so he can hit me with a sock full of nickels or something, he's not going to get a database of everywhere I've been over the past two years and hang around the coffee shop that I have an 84% chance of visiting on the third Thursday of odd numbered months. He's just going to look up my address and wait in the bushes outside.