He was slightly off but I do agree, 1 great choice and 999,999 bad choices are better than no choice at all, with a few caveats. One, (and I'm sure Apple would do this) the interaction of a watch API with the rest of the internals/data of the watch has to be limited to only what it needs. Perhaps the API would allow the developer to build the customization placeholders (weather, calendar, etc.) into their design. Second, the watch faces should be treated with as much scrutiny for approval as their iOS apps. Finally, allow users to interact with a watch face via the App store or iTunes before buying to make sure they can weed through the crappy ones.
"Leaving it to Apple" is something that could have been said when the original iPhone came out without an app store. Yes, Apple makes incredible apps and there are an incredible amount of really crappy apps in there by developers who don't know anything, but there are a few which exceed Apple's own apps. Perhaps there's a developer/designer out there who has an idea for a watch face that will blow Apple's out of the water.