They want to kill it fast because streaming customers are more profitable. They want you to switch from physical media to streaming NOW.
Yes, yes, I know you can't get that esoteric or new release by streaming. There's a ton of stuff that never made it to DVD that is still on VHS or Beta. I don't see you crying over that.
Netflix knows this. They are accelerating the switch and they're doing that by killing their DVD division in the most horrid way possible. That game rental thing is a bone meant to mislead you and is absolutely pointless. That part of the rental industry is being killed off by Steam. They know that too.