It’s possible to read devices’ battery state and many people have automations or dashboard widgets that display a list of batteries that need changing, but why can’t Home Assistant tell me what battery I need? And even better, give me a summary of how many of each battery type is in use in my system so I know approximately how many of each to have in stock?
(acknowledge that populating this data would initially be quite challenging, but it could be crowd sourced - I’d be happy to add the data for all my devices for example)