Very, very true. I was a child in the public school when this change was beginning in the late 50s and early 60s. I saw it happen. History and geography were turned into junk. Now everybody's acts surprised when Americans don't know any geography or history, and nobody can figure out why. It's because neither subject has been taught in the schools for years (especially geography), that's why. Such a mystery!
Sort of like why can't kids read nowadays, when the schools refuse to teach phonics. During the early years of my schooling, using phonics, virtually every kid learned to read. Over the same period I cited earlier, phonics was gradually phased out in my school except in the classes of the older teachers who kept their old materials and refused to stop using phonics because they knew how well it works. Over those same years, more and more students (those who weren't lucky enough to have the older teachers) had trouble learning to read. Another big mystery!
What you say about phonics is very true. The loss of phonics instruction is the main element in our children's failing standardized reading tests.
And then the mathematics organizations (who tell our government which textbooks Title money may purchase) decided that memorizing addition and multiplication facts harmed students' psyches. So, this requirement had to be dropped from math classes.
National education organizations have systematically ensured that students fail in our public schools. The reason for the manipulated failure? Lower scores = hue and cry for more teachers = more teachers hired = more union dues and more union insurance policies sold. $imple arithmetic.