If anything, if that was actually true, it'd be a colossal indictment of prior generations of administrators and leaders demolishing the quality of education for those who followed. So for GP's sake, I hope they're actually wrong about math skills being weaker among the current gen.
Every high-end school getting lots of applications does mean more students are seriously trying for college, and yes, the same student in 1975 would have a harder time being admitted to UCLA today even if it's just because they're flooded.