Garmins are incredibly expensive and not everyone wants a fitness tracker. Garmin's UX is also very disjointed between devices for how expensive they are. Plus, battery life tends to be garbage for smartwatches. I just sold my Apple Watch for a Coros because I was tired of trading battery life for features I didn't want/use and Garmins also require
yet another subscription for some features. As someone who just spent the last month deciding on a new fitness wearable, much of the market is full of bloated devices that don't do everything right, but instead do a handful of things right with a laundry list of caveats.
There's still a strong market for dumb watches too, so a long-lasting "smart" device that does some things but not as much as an Apple Watch, Garmin, Coros, etc while still serving as a general information displaying wearable sounded enticing. Unfortunately Apple's lockdown of the iPhone for the previous Pebbles (which I think might still be a thing) and my need for fitness tracking are what prevented me from buying a Pebble.