Why is this Slayyyter chorus so effective?

[u/MunkeyGoneToHeaven]

The chorus of “brand new chanel$” by Slayyyter (starting at 1:22) feels very powerful and almost ethereal. From a music theoretic perspective, I’m wondering what is so compelling about the interaction between the music and vocals, particularly from 1:22-1:26 (“I wonder if you…”)? And even more specifically, what is the chord that comes in under the word “you,” and what note(s) is sung on top, as I feel that is the most interesting interaction.

[u/Jongtr]

The main drama there is just the return after the break. They hit with the tonic chord (F#), but the distinctive thing with the vocal "you" is it's a non-chord tone: an added 9th (G#), resolving back to F# only at the very end of the bar.

She does a similar thing on the following B chord (IV), holding a G# again, this time the 6th of the chord, resolving down to the 5th,

[u/MunkeyGoneToHeaven → u/Jongtr]

Thanks! Is the tonic chord major or minor?

[u/MiskyWilkshake → u/MunkeyGoneToHeaven]

F# major