While wireless derailleurs may offer fast and precise electronic shifting, the things ain’t cheap. That’s where the NXS system comes in, as it’s promised to make existing cable-actuated mountain bike derailleurs wireless for less than eighty dollars.
I’ve had to touch the derailuer on either of my MTB a grand total of once a year when I give them a once over for maintenance, or when I eat dirt and rip them off the frame - not the drivetrains issue there though, purely rider skill issue.
It rather tweak a cable once a year, or heck even a few times a year than charge a battery every few weeks.