I’ve seen a tablet for old people. The whole interaction is limited to NFC cards. Instead of having to open an app to start a video call, you put the Call Flipper card in a tray. On the other side I can send pictures which are then displayed for her.
My 95 grandma would never have been able to use a smartphone/tablet otherwise.
Matrix still has it’s problems. All the meta data is still saved on every server permanently.
There is still space to improve from there.