Currently, about 60 million people in the U.S. labor force have a Bachelor's degree or higher. This is almost 42% of the labor force, up from 26.2% in 1992.
From Calculated Risk.
I graduated from college in 1992. My daughter graduated from college in 2020. My degree set me apart from the pack a lot more than her degree did, although it helps that both of us graduated in three years from highly selective liberal arts colleges with STEM degrees.
But I am very skeptical that the quality of the workforce has increased all that much because more people have earned college degrees. I assume that the shift is mostly degree inflation.