Bzebabe is right! Having a number 1 today vs a number 1 10, 20 or 30 yrs ago is like Janet having 8 real diamond rings, vs Rihannas 9 diamonte rings, but because they both sparkle you are saying they are the same. Diamonte is easy to get, Diamonds are not.
A superstar can sell albums, singles, tours, - the whole deal. These days the gurls seem to ba able to do one or the other but not all 3 so lets not even try to pretend they are in the same league as the Divas ever were. At Madonna or Janets peak, if things were as they are today, every single one of Janets songs would have been number one. She would be having about 30.