What? The SR-71 was a strategic reconnaissance aircraft. It was not, and never was, an interceptor. And the F-35 was never tasked with replacing an interceptor, but is a slow-ish multirole aircraft with a heavy emphasis on strike capability. And the USAF hasn't had an "interceptor" in decades (single mission, short range, high speed, point defense aircraft).

There was a YF-12 interceptor prototype that was a variant of the SR-71 prototype (A-12).

Makes sense, the SR-71 has never intersected with any interceptor program. And the F-35 is perfect for its role (whatever it is) which is very much relevant for the current theaters. There is no embarrassment whatsoever.