Very specifically? The whole reason we are even having this conversation is because it was not specific enough. Why didn't he specifically say "the media" instead of "the left"? Or "the left leaning media" or "liberal media". He didn't. He just grouped everything up into political rhetoric against his perceived enemies and Robin Williams' death became a literal weapon for his propaganda campaign.
I agree with you that Rush is wrong about how the media is reporting this. My days off are spent with the TV on pretty much all day on NBC and I have seen nothing but heart warming tributes everywhere. Nothing about dissecting his condition or reasons for his death.