Warframe is adding a nice open world to the game. I've played the game a good bit and it's massively better than it was a few years ago. This might raise the bar even higher for D2 expectations for some players. I know a sizeable portion of the Destiny player base played Warframe and enjoyed it.
EDIT: I never said Destiny killer. I believe games tend to kill themselves. Ironic eh?
-
Warframe has been around for a while IMO it didn't do much to compete with Destiny, best case it props up in the forums when people are feeling a bit disgruntle with Destiny. However, as soon as something new is added or even an update gets released in Destiny the Warframe talk seems to no longer be on peoples minds. If Warframe was releasing its own sequel then maybe but its not as far as I can tell. TL;DR Warframe is at the point in its life cycle where those who are going to play it are aware of it and those who aren't more than likely aren't going to care about it.