Two modes.

Normal mode is story mode, it drops loot, it is harder than WoD and about the same difficulty as Second Coil (normal) with nerfs + echo.

Savage mode is the hard mode they just chose the "Savage" as it's been used before and needed something to differentiate the two, it drops loot, it is "as hard as a Final Coil savage mode".

The differences between loot is item level, and that Savage version can be dyed.

Just think of Normal mode as Story mode, and the new "Savage" mode as the mode we're currently used to. They are Savage in name only.