WYNZ's format is different. This is no longer an Oldies/Classic Hits station, playing the Top 40 hits of the 60s, 70s and 80s. Nearly all the rhythmic and pop music is gone. It's mostly a Rock-leaning Classic Hits with some oh-wow Alternative hits.
The only two African-American artists I heard were Stevie Wonder and War, who both got plenty of play on Album Rock stations in the 70s and 80s. You're not going to hear Michael Jackson, Diana Ross, Roberta Flack or Lionel Richie. I doubt you'll hear many general pop artists either, especially women. No Carole King, Olivia Newton-John or Carly Simon.
It's mostly Rock hits of the 70s and 80s with an occasional 60s Rock hit. And it's hook is several New Wave or Early Alternative songs per hour. I heard "You Spin Me Right Round," "The Future's So Bright I Gotta Wear Shades" and "Cars" by Gary Numan. Expect to hear Level 42, UB40, Thompson Twins, Howard Jones, REM, U2, etc.
The "Rewind" format has worked pretty well on WREW (note call letters) in Cincinnati. It's currently #7 in the market.
http://www.rewind949.com But Cincinnati also has a highly ranked general Oldies/Classic Hits station too. WGRR is #2. WREW does play 90s and no 60s, so it's not exactly the same as WYNZ.
Portland now has three Classic Hits/Classic Rock stations, Frank, WBLM and now WYNZ, all competing for the same audience. WYNZ leans more pop, Frank is in the middle and WBLM leans more rock. But I'd bet the three stations share 70% or more of their playlists.