Look at it this way: a professor is, by definition, someone who has managed to achieve a specific high-status position under the present bureaucratic system for awarding academic titles and selecting people for academic jobs. If someone like that gives you career advice, there are many ways how it may end up being awful signaling nonsense despite the good intentions of the advice-giver. For example:

• Education in your area may well be a zero-sum signaling game, which however nobody engaged in it will admit. The professor will speak with the implicit assumption that by pursuing the same path as him, you're enhancing your real market value -- whereas in reality, you're wasting time and effort on signaling in ways that were effective back in his generation, but have been superseded by more advanced developments in signaling since then.

• The professor's advice will not at all reflect the real way he managed to fight his way through the system. He'll give you an idealized version that sounds like the road to success means obeying all the official respectable norms and satisfying all officially advertised standards by the letter. Yet, of course, the real story would be very different.