If rock and roll is an attitude it will never die....
If rock and roll is a musical style that goes with each generation and embodies that attitude then it has died over a dozen times only to be reborn each time- in a different musical guise- for each generation
If rock and roll is simply a musical style then it was probably dead with the confluence of Chuck Berry going to jail, Little Richard going religious, Elvis joining the army and the day the music died...certainly by late 1959 or early 1960...some might even say it was killed off because it was too threatening
If rock and roll was a style where the electric guitar was the dominant instrumental voice then it died sometime in the mid to late 2000s...
If rock and roll is simply whatever music white people appropriate from black people then it’s hard for me to know what that is in 2020