The trend is somewhat new if we look long term. The gap between PhD’s and number of openings in academia has gotten a lot worse.

It's probably worse now, but it's always been bad.

My dad got a Ph.D in nuclear chemistry from MIT between 1959-1966. He bounced between a total of 4 post-docs afterwards without finding a permanent position, then left to start an unrelated small business in 1971, then briefly went back to work in industry between 1978-1984 making solar cells, was laid off twice, and became a househusband for the last 25 years of his life.

He had a family friend, 3 years younger, who told me after my dad died that my dad had saved his career. How? "He said, 'Don't be like me. Don't go into academia and become hyper-specialized in something nobody wants. Go into industry and make lots of money.'" Friend went to work for I think Hewlett Packard, working in semiconductor fabrication research. Friend had a nice house in Cupertino, raised 3 very well-off children, retired in the 80s. Never knew how much he made, but he said "A lot".

Between 2010 to 2015 my top 20 ranked university had 1 permanent job per 50 graduated PhDs in physics and maybe 1 in 30 for mathematics.