They are still at their peak. Britney Spears almost always succeeded in losing weight. When she returns to the music scene, she has to be crowned. Beyonce got married in recent years, gave birth to a baby, left the group, worked hard by herself, sang songs for Obama's wedding, and got her own fashion brand. Their grades in recent years will be worse than when she first debuted, especially Brit. But first of all, when they made their debut, teenagers' pop music dominated the music industry, and the whole record industry was a big hit. Their sales performance is certainly high. So far, Brit still occupies the number one position in the first week of sales of female singers' albums, but now, the music industry is shrinking. They are definitely worse than in the past, but they are still very high compared with anyone else. Second, when I first started out, artists would try their best, but they have been working hard for more than ten years. They should have status, prestige and honor. They used to sing saliva songs to cater to the public and increase sales. Now they guarantee the quality and quantity for themselves, and people can't understand high-end things, which will also lead to their own grade decline, so they only fight for popularity, prestige, experience and status.
So, I don't think they left the peak. What you said about their peak period is that they want to build a reputation for themselves, publicize everywhere, take programs on announcements, and let everyone know more about themselves, accept themselves and like themselves. But now they have reached the peak that their names have become a slogan of the times, and they can be listed without any publicity. Concerts can be quickly robbed without any creative tickets, just on the programs they want to participate in.
Don't take things too lightly. Actually, Beyonce and Britney Jean Spears are not on the same level. If the landlord had known them better, he wouldn't have put their names together.