Maybe, but I've seen more controllers destroyed by AA batteries that leaked and corroded the contacts than internal batteries that failed.

It’s good that we have decent NiMH batteries that I don’t think leak like alkaline ones do (I’ve never seen one!).

Lower voltages, but flatter discharge curve so pretty much everything works with them.

Let me guess: were they alkaline batteries, left in the device while not in use for several weeks or months?