Do you mind explaining why you think such advice is BS? I assume there are at least some people who are exerts, or who have experience, who're worth talking to?
That is a good thing to listen to from an expert. I should have maked explicit in my comment that I thought it was a great thing to do from the author.
But the key point is that is always BS when the person you are talking to thinks he knows better about your business than you. And that there are some obvious thing you should and you aren't doing it that will fix your startup. This could happen with random people too - the same way an expert can be humble as the author new attitude - only is more common with experts.
I think the objective answer of why I think is BS is that an arrogant interlocutor, almost by definition, lacks empathy. If someone is sure about what your problem is, it is probably because he didn't actually listen to you, he is picturing you as a straw man and giving advice to it.
This is an interesting formulation, and I think there is something to it. "Fake" experts are (all to often) merely people with "too much self-esteem" and too little comprehension of context. "Expertise" is too often a crutch for those looking to assert some sort of claim to social rank or status. Or, polish their "brand" for future 'business opportunities'.
The flipside of the analysis, however, is the juxtaposition of "objective" with "lacking empathy". Both are two ways to de-emotionalize a subject, and it is a good rule-of-thumb to ask if what you are seeing is one or the other. Also, to make sure you have enough resolution to distinquish the two variations. After all, it is quite common empirically for people to become emotionally attached to home-grown ideas,[0,1] and this is in fact quite common with startup founders [2].
What is juxtaposed here are insiders and the outsiders both of which are fighting for credibility and influence. And ultimately, the prize of "being right". There are times when having high-powered incentives and/or low-powered incentives either work or don't work in bringing to bear a new light on the subject.
Ultimately one needs to be a ~visionary (not run of the mill), or truly from left-field.
[0] "Not invented here syndrome"
[1] There is an emprical behavioural bias about "switching" opinions, even on trivially important positions, provided that the information on the position has bee made public to a peer group.
[2] Which, if unchecked, classically leads to the installation of a new CEO.
When I use a product, whether it's a blender or a website, the producer's business goals aren't really my problem. If I communicate to them at all as a customer, my only relevant area of expertise is how I use their product. (And possibly how I would like to use their product, if it were improved in some way I would prefer.)
But when they say "here are the things I tried in this circumstance, and here's how they went" then they're reporting their actual experience (rather than imagining yours) and you are able to take their actual experience and apply lessons learned to your actual experience.
[0] in aggregate -- while any given piece of advice may be helpful, other advice may be the opposite, and there is no reliable way to determine which is which.