” Its usually the intermittent beeping that tells you the 9v battery needs replacement which is the problem in most cases.”
I learned that the hard way many years ago, and that’s mostly the first issue that needs to be solved: buy a new battery
As a Boomer, I grew up knowing about auto mechanics and simple fixes for home problems. When my first smoke detector started with its intermittent beeping, I figured right off it was a low battery warning. A lot of electrical gizzmos do that or a flashing light.
Without their parents at home or their custodians in school, Millennials and Gen-Z would stumble around in the dark if a circuit breaker tripped. Most are metro-males and wouldn't get why a heavy item they hung on the wall fell out of the drywall. Think studs (yes, pun).