Your statement is incorrect. Only 1 in 5 Nevada high school grads who opted to take the test passed. The top percentiles likely go to college instead of enlisting. But, I will grant you the education status in the USA needs improvement.
The last I heard from military officers is that the pass/fail point is moved up and down based on hiring quotas, and varied from service to service.
What's "shameful" is that Selective Service is on hold rather than being used to guarantee 0% unemployment among 18-20 yoas.