That sounds less like "this device will never do these things" and more like "it will take some time for us to port software to do these things to this device." Which doesn't strike me as unreasonable, given the scope of what they're trying to accomplish.

And since they're building on existing open-source systems like GTK and Flatpak, if you don't want to wait for them to port a calculator to the device, you could presumably port one yourself. The source for GNOME Calculator is right here: https://gitlab.gnome.org/GNOME/gnome-calculator ;-)