There's this tendency on ATRL to overestimate the importance of the Hot 100. Having a hit is very important, but status, relevance and album sales are also indicators of who's bigger and Ariana wins / will win in all of the above.
Think they mean the Pre-order Chart.
Meghan is #7, Ariana is #9, 5H is #31.
But to be fair, Meghan has a 2nd single and 4 promo singles out so that obviously will make it more popular ATM.
Ari also has 2 promo singles.
5H only has 1.