To create an analogy, my car doesn't have bullet proof glass, someone could easily shoot it up and i'd be dead. But nobody really goes around shooting up cars, so is it an issue?
(= just because something isn't in widespread use yet/maybe hard to do doesn't mean it isn't used in targeted attacks. Or might become widespread after new discoveries or in combination with other vectors. And a lot of her work (e.g. Qubes OS) aims at making things secure on a very low level)
Also, some of these features are marketed and sold to us as additional protections, and I think it is important to see if they can actually do what they promise or if they just add complications, especially if they inconvenience users.