Like, huge stars of yesterday can`t make a dent in hot 100 or billboard 200, they`re dominanted by early 20`s and teens musicians. Mariah Carey last year flopped hard with her album, Madonna flopped with Rebel Heart an its singles. Older rock bands don`t even appear anymore, Rolling Stones new album also was a huge flop.
I think its because when the fanbase mature, they like to stick to the older songs and albums, and don`t care that much about the new releases from their artists, but they still pay huge money for concert tickets. The younger artists have young fanbases, wich consume everything their idols throw at the market and go on downloanding songs, streaming, and making those events to watch youtube clips to make their idols go to the top.
Old people like old things and don`t care about the new things as they always stick with the thinking " Oh, my days were the golden days, now everything is shit", in 20 years we are going to say Nicki Minaj was a great musician and the singers of the time sucks, it may be the old cycle again.
