It isn’t a massive issue tbh. My wife wanted one. She’s had it since December and has only needed to charge it like 3 or 4 times.

A replaceable battery would be a good feature, but after years of different mechanical toothbrushes I don’t recommend choosing based on repairability. They almost all seem to just keep working for ages, and by the time something breaks they’re so nasty you’d rather buy a new one anyway.

Fun fact, my kid used to call them cannibal toothbrushes. Toddlers are fun.