Sorry if you are disappointed.
We definitely will have a user replaceable battery. It will not be soldered to the board nor glued into the case. But it will involve some minutes of work and probably also some tools (screw driver) to replace it. So the obsolescence issue is limited or none.
Give the size constraints we have we have no other choice to not have it more easily removable. I somewhat agree that this would be the favorable solution but it would turn the mechanical design into a nightmare.
Cheers
nicole