Good issue to raise. Many of us have given advice to young people (undergrads, grad students, mentees) that EA had a lot of secure funding and EA-related careers would be great to pursue -- especially as an alternative to the usual academic tenure-track research route. That all seems open to question now.
Let me offer a perspective from academia; I don't know about mentorship in other industries.
To put this FTX funding crisis in context: many professors take on far more graduate students than can ever get a tenure-track job. That, to me, is far more immoral than encouraging young people to consider EA-related careers. Academia perpetrates the myth that a PhD is the royal road to a professorship -- when in fact, the odds of becoming a professor, even contingent on getting a PhD, are now very low.
More generally, academia is facing a serious long-term funding crisis, with declining student enrollments, a catastrophic drop in male students, and a crisis of public legitimacy (given the culture wars). I would not be surprised if many universities shut down within a decade or two. A few may rise to replace them. Academic jobs might become even scarcer.
I think it's important to express all appropriate epistemic uncertainty about the funding and opportunities available in different career tracks. Mentors should take their role very seriously. We have a moral duty to become well-informed about the likely outcomes of different career tracks and personal priorities -- not just over the next few years, but over the many coming decades when our mentees will be working.
Be honest with your mentees. Share your feelings of concern and diminished confidence. Your value as a mentor isn't that you have nothing left to learn; it's that you're slightly further along the learning process and you're willing to share.
So, here you are, learning your way through the current crisis (as we all are!). To my mind, the advice and guidance that you can offer now is even more important, because the lessons that you're learning (against hubris, towards greater humility and carefulness) are worth sharing.
Model the behavior you want to see in your mentees. Don't quit now. Learn and try to to better.