It did well enough, but the fact it didn't become a smash was not because it had no promo or it was a bad song.
I think AH's singles are gonna perform similarly to Ed Sheeran's divide era: SOY/BL became monster smashes and they caused the subsequent singles (IYE/Galway Girl) to underperform because they were overshadowed. Almost a year after the release of the album, another single can become a massive hit again (Perfect/SYT). I don't think SYT is gonna be anywhere as big as Perfect tho.