Garmin does far more than that. On to of basic running features, their watches have full cycling functionality, including pairing with additional tools (e.g. HRM, Power meter, etc.). As well, swimming, which is an absolutely massive strength they have over everyone. Both in pool and open water. My Garmin device has profiles for skiing (XC & downhill), hiking, climbing, trail running, treadmill ru nning, bike turbo trainers, stand up paddle boarding, rowing (indoor & out), Golf (HUGE strength), and multisport. There is even a strength area, though from what I understand it is lacking a bit.It depends on the level of fitness you're after.
If you're the sort who's continually trying to optimize your pace and otherwise manage every nuance of your fitness, then definitely go for Garmin. But not everyone is aiming for that! Some just want to know whether they're being reasonably active, record their runs and otherwise get motivated. For that, the Apple Watch does a good job. Google Fit is getting there, but it's still a bit rudimentary in comparison.
I agree that if you're not into fitness it probably makes no sense, but if you have any interest in fitness, going with any other brand just makes no sense.
edit: plus step counters, on-wrist HR, calorie tracking, etc.