That's true for smartphones (I had bad experience with Android from 2 big vendors which stopped updates around end of sales date) but many other battery powered devices don't need regular security patches.
For me, this limitation applies only to my phone. I have plenty of other wireless devices and deliberately prefer devices that can use AA batteries. One reason is that I don't have to manage the multitudes of internal batteries as much and I need only 1 battery charger with batteries always ready to go. And obviously, battery going bad won't make my device useless (My DS4 controller's internal battery went bad in about a year. So I'm sticking with xbox controllers.)