No, I absolutely disagree with both, EnergyNumbers question and his answer and the from MSO imported term "broken window" he uses.
The limited number of such big list questions about important study material for students and researchers should just be well curated, since the site is intended to be useful for students and researchers (according to what is written in the About) who need to learn things and often have to familiarize themself with new topics in the course of their live as active and flexible researchers.
Questions on spezialized and/or well defined by the targetted level or otherwise localized study material (including books if needed), such as about twistors or other minor subjects such as this for example, for which not a large pedagogical literature and tons of books exist (as it is the case about broad topics such as statistical physics, quantum mechanics, qlassical mechanics, etc) exists, should be allowed and tolerated as it has always been the case until the end of 2012. Such well defined requests for study material are neither bad (their answer is helpful for many peopl) nor open-ended as EnergyNumbers claimes, since there simply to not exist that many books / turorials / lecture notes / introductions on Arxiv etc, that fit as answer to a well localized question.
The only issue (in fact a non-issue!) is, that somebody should take care of adding the new specialized questions about such study material to the corresponding lists, such that things are systematically ordered and well organized. Apart from this, there is absolutely nothig to "fix". I could curate and regularly update the lists of study material and I would do it if it helps.