As a result of MC-272122, the main menu panorama for 1.21 is missing a ladder at the bottom of the left ladder shown within the room. The screenshots show the main menu panorama with the missing ladder, with one screenshot edited to circle the location of the missing ladder.

Edit: I have now seen Moesh's comment on MC-266441 stating that missing ladders and some other missing blocks are deliberate and intended for the player to replace. Therefore, I think this is likely Working As Intended.