more popular than...themselves? Information I've seen, with 3 months left to go in the year, currently puts the Beatles on track to be the best selling artists of the 2000s. Which would make it two decades in a row. And the 3rd decade starting from the 1960s. Seems kinda obvious Michael Jackson would have the '80s wrapped up...but who owned the '70s? Elton? The Eagles? Ted Nugent? John Denver? Wings? But don't let's forget the big Beatles resurgences in 1973 and 1976. Good question...and no, I don't have the answer.
Re: more popular than...themselves? Because Garth Brooks whored himself out during his rampant ego days...with his $25 box set, etc. Then he got his assless chaps handed to him when "Beatles Anthology" debuted at #1 and he didn't. Then started throwing hissy fits and demanding that everyone at Capitol be fired. Thank God he's retired. Most sensible thing he ever did, and he knows it. (Far more than his announcements about taking a year off to devote to world peace or becoming a major league baseball player.)
Re: more popular than...themselves? Anyhow...mayhaps the Bee Gees might have dominated (even if they come off more submissive) the '70s saleswise. Always thought that Abba's sales figures were way overstated, especially since at the time they claimed to be the top sellers of all time, they'd made less of a dent in the world's largest market than Three Dog Night or many others. And once they had...more of a singles act than albums. Which is why when it comes to sales figures, no one mentions Abba anymore.