There aren’t any decrescendo songs. I’ve never heard a hit (or any other song) start really huge and then get smaller and smaller until the end.
Yes, some songs are a bit more static than others but there’s always a trend…wherever the song starts, by the end it’s at its biggest.
So make yours get bigger. The last chorus should sound elevated from the first. I should be able to tell it’s the last chorus and not the first.
All your favorite songs crescendo. So make sure yours do too.