Joy, I typically respond with something along the lines of “if Hozier and the Lumineers had a baby, that’s what you would get.” And, their performance at TD Garden on Sept. 20 solidified this notion for me more than ever. Although that was arguably a more intimate experience in the hills of upstate New York — before they were selling out at venues like TD Garden — the song still held all the emotion and nostalgia in the TD Garden nosebleeds as it did up close three summers ago. For the middle part of the second set, the band took us back to 2018 and 2020, playing a series of songs from the albums “Mt. Joy classic: songs named after people. As the band “closed” out the night with “Astrovan,” confetti blasted from the stage, lighting up TD Garden with color.