I'm astonished anyone even asks that question
Just because there is a technological option that depends on batteries or a power supply people think they can do without a tried and tested analogue alternative.
In many cases it is true, but I've seen systems fail too many times, and, let's face it, when they go down it isn't going to cost you £18 to replace
I do worry that some pilots are so in love with the technology, they are handing over too much control to the systems and fail to remember that it is only a tool.
Anyway - rant over......