Your question perfectly illustrates why genres are useful as a means of discussion of sounds and styles, but useless for actual categorization of artists, bands, albums, songs, etc.

Historically in America, the people responsible for innovating music did so because they didn’t give a crap about fitting within a particular sound. They made the sounds they heard, that grew out of what they knew, and made newer things from them. From Duke and Charlie Parker to D’Angelo and Erykah Badu, people who push music deliberately eschew the constraints of traditional labels. And perhaps Steely Dan isn’t so influential as the people I’ve named, but they pushed the capabilities of their sound for sure.

Ultimately, trying to pigeonhole artists into singular genres is often not only impossible, but harmful. I’ve talked to many a friend who had difficulty properly getting their music out there because they didn’t write it with a specific genre in mind, yet streaming services tried to get them to define their sound under a singular banner.

Which, if you didn’t know, is how many genre distinctions came about in the first place. For the most part, it was not musicians who first labeled genres; it was execs and managers who wanted to slap labels on things to make it more easily marketable.

All that said, you’ve actually answered your own question here. You’ve defined the elements you hear in their stuff, and that’s as far as it’s gotta go.