No, it really isn't. A dedicated device that requires you be near it in the case of the tile, or another iPhone owner be near it to update its location, and can be relatively easily found on one's person and removed from someone's life is way less dangerous than, say, a hidden app that a stalker installs on their victim's phone without their knowledge. No physical device, no physical evidence, just a little tiny piece of software that just phones home to the stalker to let them know where your phone (and you) are. I've seen this shit dozens of times when working in tech support. At several times in Android's history, it was super easy to make this shit entirely invisible outside of the apps list in the device settings and even there, list it as though it's a core piece of device software, like some diagnostics or specific settings sub-app. It's also been possible to install things like that remotely at a few points.

So, no, this is actually way less dangerous than a cell phone could be, but could theoretically have a lower barrier to entry for someone who wants to stalk someone, but doesn't really want to put in very much effort, I suppose.