Suppose you know that only 1 in 10 PhDs in your field end up in a tenure track job. A decent fraction of your classmates are interested in industry--or never want to see the inside of a lab again. Maybe this reduces the competition down to one in six or seven. You're in a pretty good program, definitely in the top 15 percent of the field. It's certainly not that easy, but...you're not obviously worse than most of your classmates, you work on a hot topic and you work hard. What are your chances?
Very few grad students get any kind of personalized career advice or discussion of their prospects. They should obviously think about this, but more senior scientists also have a responsibility to provide mentorship and frank assesments.