The U1 chip in the Apple Watch Series 6

I know that Apple has installed the U1 chip for Ultra-Wideband into the Apple Watch Series 6, but I am curious what it does. For iPhone, it allows a more precise AirDrop (locating other U1-equipped iPhones), a new handoff interaction for the HomePod mini, Apple Car Key, and Precise Finding for the new AirTags (probably missing something here, you are welcome to add other functions that I may not know of). But other than the Apple Car Key, all of the other functions mentioned above are not exactly available on watchOS. So what's the current purpose of it anyway?

Thank you all for your replies! It really helps! ;)