I can see usb-c being convenient for a smartwatch, but for a fitness watch they you are going to wear while hiking, swimming or any type of rugged outdoor activity it is important to not be a hole that can get a bunch of stuff stuck in it. Unlike proprietary cables for smartphones of the past the connector on high end smartwatches aren't there because they are trying to sell you a bunch of expensive cables and accessories that use that port.

As I mention in the post, there's an integrated rubber lug which protects the port.