Yeah, that's a good point. If the whole advertising landscape forcibly moves away from direct targeting, presumably the same players retain the same position in the marketplace they have now (with the possible exception of ad dollars moving to other media if web is seen as less effective in general without direct targeting).
Since they do such a terrible job of it anyway I can't imagine it being less profitable.
And then again, maybe actually paying for something like facebook is the right way to go.