Honestly, I do not see much shock in writing a song in 3 hours, I mean, I can do that.

Though many successful songs were written in less than a hour...under 30 minutes even. If you know what you want for your song and it turns out well, then spending ~20 mins on a song is not even unbelievable.
It's also not such a short amount of time to go "So that's why it's so bad lol!!1!". I'm not a fan of the song myself, but I don't think I would be even if she spent her whole entire 3 year hiatus trying to make this one song her magnum opus.