A little google voice magic, or any number of other SIP providers and apps will have you making calls to POTS numbers over just a data connection very easily.

No. I and 98% of the world just want to make calls, not start a project.

There's a reason Linux is not ruling the desktop, and that there is it.

Turns out that such functionality is actually supported natively by the watch. https://support.apple.com/en-us/HT203032 as long as as you have any of these carriers: https://support.apple.com/en-us/HT204039

Though to your point it did take me a bit of ducking to figure this out. Seems extremely straightforward once you know it exists.