Odds are whoever gave the threat would not have followed up on it. However, online harassment is a real issue that should be (and is being) dealt with. Besides, a threat on this scale falls into the realm of domestic terrorism and definitely should be dealt with.
Yes, some of Anita Sarkeesian's arguments are too generalizing or flawed, but that does not warrant the terrible threats she's received. Holding a debate or discussion would be a much more appropriate method.
Harassment isn't a gaming only problem. But it needs to be addressed within the gaming community otherwise the problem will continue. Ending harassment completely is unlikely to happen, but at least we can try diminishing it as much as possible. Jerks are everywhere, but it would be nice if there were much less jerks in the gaming community. It would make online experience less stressful.
My favorite glitches are the ones in Skyrim and Fallout 3/New Vegas. Seeing a mammoth hovering in the air or launching a gecko 60 feet in the air is very entertaining!
Anita Sarkeesian did influence Neil Druckman's (the creative director of The Last Of Us) decision to create more in-depth female characters in The Last Of Us. Urging game creators to depict female characters more realistically and fairly was one of Sarkeesian's goals, so she has made a positive influence here. She was also awarded a gaming ambassador award which was presented to her by Neil Druckman himself. You can watch the award ceremony on YouTube.