Streaming era is a mess. Because for example, if Adele sold 3,3 million copies of 25 in 2015 in the first week, it means that every song on this album sold 3,3 million pure sales that week too, so it would have been her in the entire top 10 too. We can’t put all the songs from an album in the top because that album was the most popular.
Same thing would have happened to Britney in 2000 with Oops. 1,3 millions copies sold first week, so every song of the album sold 1,3 million copies. It just doesn’t work like that…
Billboard needs to do like the UK charts. No more than 3 singles by the same artist in the top 10 with this messy streaming era.