I know the Ultra has an extra button, but I wonder if you can start a run on it in the rain (ie without using touch). That was what finally pushed me away from Apple Watch, and the marketing of the Ultra is quite funny if it doesn't solve it.
ANT+ is still very much present in the cycling world and likely won't go anywhere. While most sensors and devices will also support bluetooth it seems to be a much more fragile and problematic connection. From my own experience I'd always opt for ANT+.
