"good objective feedback" - right, I think advice in general is bad because it tries to bite size a complex system, that is society/humanity. Feedback is giving someone information they can act on, along with the rest of context they have of their situation. No need for you to know them deeply, just the interaction.

There are things that can work, and things that likely won't work, and most people know these. Then there is a space of things that usually work and things that may not work, and you can't fit these into a person without knowing a lot of variables about them and the environment around them, like what and who they know, their personality, their competence (not just their resume), and many, many other variables. So advice defaults to guessing most of these variables to find some direction.

And I think it boosts advisors' ego, makes advisees feel temporarily better, even motivated, but YMMV by a lot.

This is why the good advisors also change the variables in your favor, like introduce you to their network, coach, etc. And often this costs you something. Like money, equity, whatever.