Eva, yes it is the display. And I no longer object to it, though as a genealogist who is accustomed to thinking of women primarily by their birth name, it is confusing and annoying when in some of the WikiTree functions to be told I am merging or doing something else to Mary Smith when I know and think of her as Mary Beall.
But historical truth has to prevail. If Mary is addressed in documents as Mary Smith, then that must be recognized. Certainly in historic US Censuses, the man is presumed to be the head of the household and the whole household is presumed to carry his last name, so if you are doing a search, as described above, all you know is that her name was mary and she is married to John Smith, so you're going to look for Mary Smith. What I do object to is what happened in this conversation -- someone assumed that since a woman was married, she took her husband's name. We cannot make that assumption, and we should not make other assumptions without identifying them as assumptions.