Article for context:https://www.theverge.com/2023/9/12/23870522/iphone-15-pro-max-thread-smartphones (Ik that I am talking about multiple companies when I refer to android companies but many singular companies make more innovations in the phone space compared to apple)
They aren't out yet (so there's no word on if they're good or not), but pebblebee is making trackers that are rechargeable.
Not quite "user replaceable batteries", but in my opinion it's a better execution better than a purely disposable device -- so long as the battery life isn't garbage.
The chipolo has a replaceable battery.