They should stick to teaching and coaching.
We are not guru's or life coaches.

I don't think this is an easy question to answer... It depends on the individual, the relationship and relevant experience and most importantly, if they have been asked for advice! Sometimes people need someone to bounce ideas off, sometimes they need someone to listen, sometimes they just want reassurance and other times, they genuinely want to hear what you think about a situation. The only caveat I would give, is to stay in your lane... Only offer advice if asked and only if you actually have some real experience that may be beneficial. And always recommend others to seek expert counsel!

Perfect way to end your response.

Thank you sir!

I think most sane people would go with "stay in your lane"

But what I really want to know is what's with the blue and white coral style belt in the articles first picture ... I have exhausted my googling abilities.

Someone is trying to be different.

It's classic Dunning-Kruger effect. People who are experts in one domain of life tend to think they can be experts on all aspects of life. You see thin in universities where experts in the minutia of their specific field sit on committees and think they have valid answers to problems they have no training in. This isn't to be confused with the popular interpretation of Dunning-Kruger in which people think incompetent people tend to over-estimate their expertise in a given domain.

Final thought, your coach is about as valid source of advice as anyone who is not an expert in the specific area of concern, even if your coach thinks they know what they are talking about. This being stated, I talk to many non-experts about issues every day and think they likely all run the gambit of wisdom and bullshit which I just ignore and accept that everything should be taken with a grain of salt.

I'm a black belt but I''m also a 45 years old guy who got some things right and some other things wrong. If I'm talking with my gym's people about "things", I don't see why I shouldn't give my opinion or my advice on something we are talking about, if I think I have an opinion or an advice, granted that the same can be said of any white belt who could have advices or opinions more valuable than mine in fields others than jiu-jitsu, and that we are just talking, I'm not forcing on anybody my views or how I think they should behave. As long as there's no cult-ish stuff going on, we are just people talking to each other and sharing opinions and jokes, which is what should go on in a healthy community environment.

The problem would be to take advantage of a perceived position of authority, to establish oneself as guru/leader, which is different from merely "giving advices" in a informal environment around the more formal class/school structure/whatever.

It's funny I have always hated the cult of personality that comes up with martial arts. I have always hated the whole title thing for years I insisted i was just Phil but relented in my mid 40's because it seemed as I got older people especially the 20 somethings seemed more uncomfortable than in the past so it became call me Phil or coach.

It's funny when I was younger and first started teaching people would ask all sorts of advice and I would say I am a border line psycho who fights good my answer is hit it or choke it and if that don't work kill it.. other than that you are better off with someone else.

I am also a successful businessman with a family and as I matured I realized I could share insight into what I have been through both positive and negative but to NEVER get invested in my own advice and NEVER give it unless someone asks. I realized at least for me my students are friends and if they ask for advice give it but to preface it with it's just advice.

I am extremely weird and have a strange code and would never expect someone to follow it.. It's like my diet, I am a vegan yet tell people not to go vegan all the time unless they know what it entails

100% agree. Having a black belt means you're good at BJJ, nothing else. It would be a like a lawyer deciding that after they pass their bar exam, they should go to the local hospital and help out with heart surgery.

Now, that's not to say that a coach can't be a positive role model or whatever. But they are not therapists, that's a specific job that requires specific skills and indeed qualifications.

I'll echo a lot of the sentiments here and say that I don't think you should necessarily solicit or adhere to personal advice from your instructor. Yes, they may have some life perspective, but they may not have relevant life perspective for what you're seeing or dealing with.