I guess some would wonder why the R&RHOF has already inducted Sam Cooke, Everly Brothers, The Coasters, Roy Orbison, Bobby Darin, Al Green, Brenda Lee, and OMG....The Bee Gees. The list goes on and on of people who some wouldn't consider R&R.
Like her or not, Whitney did a lot so I don't see why she shouldn't be nominated.