Hi
I know Garmin have a nav-based hardware range (I used to have the Edge 1000; sold it to part fund my Fenix 6).
However, since a mobile phone has all the same components, sometimes better components (screen size) I think we should be able to get the same route-based nav in GCM that Edge range has. I have the QuadLock mount for my phone, so couldn't fit the Edge mount anyway even if I wanted it.
A Fenix watch + Phone is more "complete" than just an Edge for me; so I can't justify Fenix + Edge + Phone (the Fenix and phone I'll always have anyway), when all I'd be getting on the Edge that the Fenix + Phone combo provides is actual usable navigation (it's not "usable" using the watch for nav, in fact it's downright dangerous).
So, personally, I'd be happy to pay to unlock such an in-app function. Currently I pay for Kamoot instead so Garmin aren't gaining anything extra from me... but they could.