Choral singing wide, pure vowels for a long time without overpowering the purity takes practice and finesse to balance well.
Pianississimo without enough effort and focus, and the pitch created wavers and won’t be sustained for long. The audience will not be on the edge of their seats.
Forte unleashed without focused technique becomes a shrill and shouted. It doesn’t appear effortless to the audience.
The thing is, it only looks effortless when done well.
Sometimes a composer intends for a singer or instrumentalist to play the struggled note as loud as it is written. And other times not.
You often have to step back to move forward.
How is the song created serving the listener? What is it trying to contribute?