I wish they would, it sucks that it's like every other game or two that you'll get a single blue item or whatever. I think it's Bungie's thinking though that the gameplay of fighting real players is the main "reward" instead of doing the repetitive strikes over and over for 5-6 engrams
The grind for loot is real in Strikes, and I always get a little excited turning in my stockpile of engrams after a hour or two of Tiger, but that's basically all that motivates me. It definitely isn't killing the same boss for the 20th time or running with silent team mates through trash mobs.
As much as the crucible can suck it's way more engaging than Tiger. If they gave me consistent engrams and rewards I'd probably never go back to strikes outside of bounties and the like, even if I was missing out on the loot dropped during the strike itself.