In general, Islamic forums are already full of these sorts of answers, and they often just devolve into apologetic and polemic debates with each side cherry-picking primary evidences that support their case. More often than not, the actual questioners just end up more confused than when they started.
The basic premise of the Stack Exchange model is to provide a better Q&A experience; cut through the noise and debate that the Internet never seems to get tired of, and just give people actual useful answers.
In order to be useful, answers need to be tailored to the question. Many of the questions on this site (particularly fatwa questions) demonstrate little if anything in the way of actual expertise in the Islamic sciences. Professional scholars can spend years — can even dedicate their whole lives — to studying how to understand and apply the primary sources and barely scratch the surface of what they need to know, how so then random strangers on the Internet?
There are centuries upon centuries of research done in the Islamic studies; whole branches of Islamic science have been developed just to figure out how to properly understand, authenticate, and apply the primary sources. And despite all this, there are still significant differences of opinion on any number of fundamental issues. The assumption that presenting the primary sources as-is, as if they in and of themselves can effectively answer any given question is at best simplistic. And just assuming that any given user is in any way capable of critically analyzing these same sources to get the answer to their question is just…no.
As I see it, the fact that so many forums — and especially polemic/apologetic sites — seem to make those assumptions is a major factor toward why people are still asking the same questions over and over again: There's no shortage of evidences out there, but a serious dearth of answers.
Questioners ask here because they are relying on our expertise, often because they lack that same expertise themselves. If critical examination of the evidences is necessary for a good answer, but the questioner lacks the ability to do so themselves, then it is incumbent on the answerer to do it for them. If neither the questioner nor the answerer show any such expertise, simply throwing more evidences into the pot really doesn't help anybody.
So, in short, no: One should never assume that evidences can speak for themselves. They are items, not answers.