Having been through Navy boot camp and Navy flight school, and multiple deployments flying combat jets from aircraft carriers, I can say this is basically true.
Boot camp involves a lot of hazing and yelling and physical abuse to separate the motivated from the non-motivated. The drill instructors make everyone miserable to get people to quit. Maybe 30% to 50% quit in boot camp. We started with 70 on the first day of boot camp, and only 19 completed boot camp 4 months later.
After boot camp, the yelling and screaming essentially ceases, and the flight program focuses on training to rigorous standards. Instructors want students to succeed. Maybe 5% to 10% wash out of flight school, often because of medical issues that preclude flying (e.g., air sickness).
The Navy has a standardized flight program called NATOPS. You can throw a pilot from one squadron into another squadron on a different aircraft carrier, and there won't be any hiccups because everyone operates the jet identically, and all procedures are identical.
That standardized NATOPS mindset is what attracted me to GUE in the first place. Unfortunately, GUE-F was more like boot camp than flight school, with abuse, hazing, ridicule - and very little education.