"Is modern jazz an oxymoron?"
No, but smooth jazz is a misnomer. It's neither smooth, nor jazz.
LOL .. so true. Although, to be fair, I think there may be one or two who are a cut above. Chris Botti comes to mind. I saw him live years ago when he opened for Sting and he was fantastic. Not exactly my cup of tea at this point in time but I still enjoy listening to him on occasion.