It's a fair question. But be warned: You're not going to get a much less diverse set of answers from them, though. I would suggest also listening to scientists who established themselves 30+ years ago. You'll likely hear a different story compared to the current crop.
In the 00's, some of my fellow graduate students did more work for their PhD than many faculty members I know did to get tenure in the 80's and early 90's. The high level of work demanded today is mostly due to inbreeding attitudes in academia. It's entirely an internal problem.