It is increasingly common that subjects of articles wish to interact directly with us and tell us that their article is wrong in some way. It is, in my opinion, silly for us to reject even harmless corrections on the grounds that they cannot be traced to a reliable source. If Wikipedia itself becomes a primary source in the process of someone commenting on "their" article, what is the problem with that from a purely factual point of view? Depending on the nature of the statement, such comments could be either incorporated as corrections (date of birth) or attributed statements (".. denies that he ever had sexual relations with that woman").
I wouldn't be surprised if such interactions are even common among traditional encyclopedias, and corrections are simply quietly incorporated (they don't have talk pages). The main problem with us seems to be making the source "reliable", but there seem reasonable ways to do so (OTRS, "update this website please", call a volunteer, ...). No, just like any credentials verification, WMF shouldn't be involved directly. But while I generally fully support the need for good sourcing in any article, I often find it absurd how people who point out simple corrections are treated.