The new iPhone SE packs a lot of Apple's latest mobile hardware, but the U1 Ultra Wideband is absent. While this chip isn't used for much now, it does mean that the iPhone SE will be locked out of any features that rely on the chip in the future.
https://www.notebookcheck.net/The-iPhone-SE-2020-doesn-t-have-Apple-s-U1-Ultra-Wideband-chip-won-t-support-AirTags.461794.0.html
"...it's unlikely to be missed by most users" I think you hit the nail on the head. These types of features are not going to be something that the market the SE targets is going to miss. If you want the SE, you're looking for the iOS UI/experience on a budget. Not necessarily all the whistles and bells that upgraded hardware would offer.
It will find my keys for me?? That's a must-have feature!
It must be grate useful in the corona crisis. The new app launched by Gov. may this feature Play important role..