I'm not sure, but these are probably the only interactive, lore related elements inside the game that don't have a codex entry. It would be a good QoL change to let us access the hidden messages from our codex instead of running Zariman missions and praying for the tiles that include them to appear.
They serve the same purpose as the other lore fragments. There is no reason (aside from taking time away from current projects) not to make the messages act like those other lore fragments.