Luke Smith even said the three of coin exotics basically just amount to legendary marks on the planet destiny podcast. The farming wasn't even that worrying because of that to them. There isn't anything in their rewards pool that's special. So three of coins is basically worthless because not only are you not going to get much new your also rolling rng 3 times. Once to get the coins, once or a couple dozen sometimes to get an engram to drop, and again to hopefully get a useful 310. The rewards are so disassociated from the nightfall and influenced by rng it isn't fullfilling at all to get 3 of coins. People want a guaranteed satisfying rewards immediately from the nightfall. Constant disappointment is going to happen even if technically 10 coins could be worth more than just an exotic right away in the end because you feel shafted right away. Taking away the legendary engrams is also a huge offsetting nerf that seems like an overall decrease in rewards on most of the rng spectrum