The new Pebbles are also claiming two weeks (they're only just now shipping, so we'll see how that pans out): https://ericmigi.com/blog/pebble-2-duo-is-in-mass-production

In any case I agree that it's crazy - particularly for Apple which tends to have pretty good power efficiency in its other devices.

And even crazier about the Garmin is that functionally they seem the same as say a Galaxy watch. Good screen quality, continuous monitoring, same or better refresh rate & overall features.

Pebble seems to use e-paper, larger design/battery to get there.