While such a site would clearly have its difficulties (see Roberts answer), it might be a good way to "contain" such kinds of questions. SO has well maintained lists of books to certain topics; so while I agree that maintaining such a list is harder for library/software, given the many questions on other networks that are flagged as offtopic indicates a demand.
It will clearly break reputation system for "most popular" kinds of requests, but those should maybe be flagged as such and not generate reputation then. I myself have often problems in finding libraries that meet rather specific criteria, and asking "can I do XXX" with this library would be much more convenient than having to try implement this with all available ones, costing many hours of work; instead someone would just say "been there, done that, works perfect".
Questions of this kind will however have really strict requirements of "well formedness", given that the requirements are stated clearly, and most importantly not just be a request of "please google it for me, I am too lazy".
These strict requirements will most likely not fit into any other site, where things are often much more liberal. I can imagine this mostly leading to a vivid discussion about the real requirements, and answers being either quick "here, maybe that works for you, I haven't looked at your requirement but saw some keywords" or only following after long discussions, not getting the reputation because meanwhile some others got rep already (mostly those answers that already have a bit reputation will accumulate more).
Also, all these questions, discussions and stating of requirements (there will be many questions with "almost similar" requirements) will mess up google search results; as such they will -- especially for smaller sites -- make the real intresting ontopic questions have a much lower SNR.
So if at all those questions should be ontopic in a rather limited area, which would be a new site. But I personally think that due to reasons Robert mentioned too, this would have a much too low SNR to be useful. A dedicated wiki with matrix tables of softwares and capabilities in high detail would be incredibly much more useful.