In the natural sciences arguing from authority is frowned on. Sure, we do have to give credence to authorities when attempting to understand subjects outside our field. But, in our own areas (and in the end with any scientific subject) authority counts for nothing. After all the best test of any scientific idea is to measure it against reality. Evidence counts more than authority.
So I always find arguments from authority weak. And when the arguer uses only that approach, maybe even using the argument from authority as a way of ignoring evidence (or even details of the argument itself), I suspect that argument from authority has become a way of avoiding the issue completely. One can end up debating at length the importance of authority, or the rights of others to have opinions, and never once deal with the real issue which sparked the debate.