Don’t iPhones pop up notifications if there’s an AirTag that doesn’t belong to you following you around?

They do.

And they'll even use RF locating techniques to draw an arrow on the screen that points at the AirTag (so that it can be found and destroyed).

Taking the speakers out of AirTags doesn't really improve the situation much; at best, it seems kind of naive.

I also have one on a office key (useful, it vanishes every few months), umbrella (useful, its left in restaurants and vanishes in the car trunk), laptop bag (useless so far, I never forget about it), and car (waiting for it to be robbed but its old)