They patched the legendarys to not turn into blues, but instead turn into materials sometimes if you whatch a purple engram decode you'll see a blue item name right before it turns to shards.

No. I've gotten weapons and armor before. It's rare but it does happen. I've gotten insanely good drops from them.

Vanguard qmaster has the harms way in void heavy machine gun

Considering how many other opportunities there are to get materials, they should never be an option when you get a legendary engram. What a complete buzz kill to get two materials instead of an anticipated legendary item!

I'd say something like 80 maybe 90% of legendary engrams I get (and it's not a lot so sample size isn't very good) turn into mats instead of guns. Which I won't mind if legendary stuff continues to use ascendant mats in the next expansion. The majority seems to believe/adamantly want all new legendary gear to require radiant mats instead though. Seems to be mostly to screw anyone who doesn't raid and thus wont have said radiant trash.

I recently got a void LDR from nightfall but yes legendary void snipers have not been a common drop for me.