No one will ever replace these rock legends. Rock music is dead commercially in America, and probably for good! Be thankful if you got to see these people and listen to their music in their prime in the 70’s and 80’s!
I serve in the Navy with mostly young 20-somethings and in addition to modern music, they absolutely devour classic rock, music recorded 30+ years before they were born. Perhaps the greatest contribution the Boomers made was in popular music. It is timeless and will be listened to for decades to come.