I think that means the watch manufacturer has high margins. For the chip manufacturer, its unrealistic to expect a profit, either way.
Because of its physical size, it won't be able to have anything more than a 5mm2 die chip. A single 300mm2 wafer can yield over 15,000 of them. 100 million devices being sold equals needing ~7000 wafers.
Intel fab has a production capacity of 45,000 wafers per month. That equals seriously low utilization. I bet you Sci-Fi writers never thought of that when they were envisioning such a future.