So far #phosh's system prompts had no way to express the input purpose as #GCR used underneath didn't yet support it, hence e.g. a SIM card pin prompt would bring up a full keyboard instead of just a keypad.
After patching #gcr, #phosh, #squeekboard and gnome-settings-deamon this is how it looks like atm:
MRs are linked here: https://source.puri.sm/Librem5/OS-issues/-/issues/121#note_180409