It's because I bribed Nielsen.
Interesting fact: before this season, there were 9 Voice songs that hit the T10 in weekly sales (mostly finale originals). There were 9 Voice songs that hit the top half of the Hot 100. Exact overlap despite the annually changing formula.
But this season, while Faithfulness got #30, Hallelujah only made it to #61, and I'd Just Love To got to #92.
Shows the plummeting impact of sales as streaming takes over.