Walk around your workplace and find someone who can name a song from "Two Against Nature" or even the album for that matter, spin the radio dial all day long and see if you hear a song from the album, ask any earbud wearing millenial if they've ever even heard of Steely Dan.
So yes, audiophiles know about it. SD fans know about it. But that's about it.
And while I agree with the Best Engineered Grammy since it is one of the best engineered CDs I've heard....that isn't exactly a big deal for anyone but the engineers....and Becker/Fagen.
wtf, underrated is another one of those very open descriptors. In a broad sense when I think about underrated I mean among the general public. That will mean a very different thing among knowledgeable audiophiles....which is probably what the OP intended....so my bad.