It's not necessarily the 'brokenness' of the system that forces people out but the consequence of producing PhDs faster than new positions are being created. "You don't have to go home but you can't stay here". No one expects that all high school students will become high school teachers. Why should it be the same for PhDs?
A lot of what is wrong with the academic system is this expectation, which is bewilderingly prevalent in both the student and faculty bodies despite abundant evidence of arithmetic skills. Faculty are often quite unaware of what happens outside their building, and students are, well, students and absorb a lot of the mindset of their role models. So there becomes a glut of post-post-docs applying for a scant few professorship, which makes getting hired and then getting tenure ultracompetitive and stressful--so many people want the jobs that the administration can ask just about anything out of them, including pretty unrealistic expectations, bad working conditions (80 hr/weeks for 75 k/yr in the sciences at many good schools) and so forth. The conditions of tenure-track professorships (when professors are still young enough to be most creative and energetic, and are still skeptical of their fields' dogma) are poorly suited to creativity and focus, so their grad students are tasked with the actual science while the professors become managers.
This isn't to say that academia is actually 'broken'. If my coffeemaker is broken, it doesn't make coffee. Academia is still making the things it is supposed to, but never in the amounts or quantities or prices that everybody wants (as it turns out everybody's wants are wildly divergent). So for this and other off-topic reasons, it's not exactly broken but definitely not optimal.
I'm of the opinion that a more optimal academy would do more to prepare grad students to find their own path, be it in academia, industry, or elsewhere. Sort of like what the US liberal arts education is supposed to be, but at a higher level and with the requisite specialization as is fitting a PhD. The critical, analytical, creative, scholarly, and technical skills that grad school can (and often does) bestow or hone are a great fit for a variety of pursuits, including entrepreneurial ones. But there is little guidance here, in part because the faculty themselves have little idea how to go about doing anything but what they do 80 hours a week.
I left the academic track after a post-doc to become an independent researcher (doing funded and unfunded research as well as R&D consulting) and it's been really surprising to see how many professors think it's an unworkable idea. Not an idea that many people try and flame out, but one so unthinkably scary that no one has seen anybody try. Which smelled like an opportunity to me, and still does...