> The culture of investing in training and mentoring to foster employee growth has been eroding for the past 40 years (if not more), to where it only seems to exist in limited capacity in legacy institutions and is completely absent in new (tech) firms. How does one convince business leaders to bring it back?

With engineers in the big tech companies mostly only staying for maybe 1-2 years I can understand employers not being very interested in training and mentoring to foster employee growth.

40 years ago engineers frequently stayed at companies like DEC, IBM, and HP for 10 to 20+ years.