Absolutely no loot when opening chests from any new structure from the Nether Update, which are Bastion Remnants and Ruined Portals. Also, if you go into spectator mode and try to open a chest that has not been opened yet, the message "Can not open this chest, loot not generated yet" will not appear, instead, the chest will show its empty content.

Way to replicate:
Open any Ruined Portal or Bastion Remnant Generated Chests. It will be empty.