Really neat story. I think one reason that the military wasn’t so keen on the design was because of their doctrine the time. Speed, firepower and EW. At that time EW was a strong suit in the arsenal. Radars weren’t all that sophisticated and the entire gamut of EW techniques were coming into their heyday. In essence, they felt they could avoid/obscure detection via standoff or own-ship EW (what’s now called EA/EP).
As radars became more sophisticated, then the area of detectability became more important.
Stealth became important because unfortunately the Cold War allowed the Soviets to build a nuclear rocket arsenal that would have requires a stealthy first strike. Stealth is only a shield unfortunately.