It's a little hard to tell from the article what the goal is. If the goal is just to use the computers as a means to some other (non-tech) educational end, e.g. as browsers for accessing online information, then Chromebooks seem like a reasonable method of doing so. If the goal is computer education, then I agree they're suboptimal; even something like a Raspberry Pi might be better for that kind of education.

One lingering unease I have about the first use-case, though, is that it forecloses some unplanned exploration. I largely got into tech by fiddling around with lightweight programming on machines that weren't explicitly bought to teach programming. Perhaps web-based dev environments will fill that gap, though; someone with a Chromebook can still experiment with anything from Codeacademy to jsFiddle to sketchpad.cc.