I'm hardly a serious runner, but I'd say the pros you laid out for Garmin are quite nice, and the cons are inconsequential to your average fitness tracker user. I'd probably argue they're inconsequential to everyone but the absolute elite and, for them, are pointless.
Sleep tracking is hard to action on for the average user outside "you slept this long" and none of the writst-based devices are that good anyway.
Pace to sub 5 is a little more annoying, but probably not useful for the majority considering most people are just running, not craning over their watch the whole time.
VO2 max is also a wild estimate, and I'd hazard it's not particularly accurate for the average person. It's off by close to 20% for me, and I should be a pretty good candidate.
On the flipside, you can get tons of data out of a Garmin that costs significantly less than an Apple watch. Plus, the majority of Garmins sold are fitness devices with some smart features, with Apple watches being primarily a smart watch. While maybe not justified (I think the Apple watch features are quite nice) I'd expect that's a major part of the reason Garmin has the rep it does.
If someone is buying a device to run, most would recommend the cheaper, light, simple, specialized, long battery life watch over the opposite. If you already have an Apple watch, it's probably a no brainer.
For the high-end Garmin devices, it's a little more complex, but not many people are considering a US$800+ device without knowing the nuances of the discussion, or having enough money to not care.