It's not a bug, 121.3a still specifically refers to a player who has no cards in library.
121.3a. The same principles apply if the player who's making the choice is not the player who would draw the card. If the latter player has no cards in their library, the choice can be taken. If an effect says that the latter player can't draw a card, the choice can't be taken.
121.3a. The same principles apply if the player who's making the choice is not the player who would draw the card. If the latter player has no cards in their library, the choice can be taken. If an effect says that the latter player can't draw a card, the choice can't be taken.