These guys have carefully crafted their image for a decade. Their online content which supposedly shows their real personality. Each member,is stereotyped, so jimin is shy and cute, a dance,genius and a flirt. Anything off character is considered action taken by the PD. The fans actually love the duality. They consider it a talent that these guys can act so opposite to their true nature. Like suga is nicknamed as cat, and you can literally find hundreds of videos on yt. The fan's mind is conditioned to think he's a calm and introverted person. So, when he shows his violent side in his solo mv, fans just love the change. Same thing happened with jimin too.
They have normalised these type of things slowly through their concerts, bangtan bombs, weverse lives and run episodes. The skinship and pairing is on another level. I believe these content which they put endlessly even milking the military enlistment is the reason of their popularity, more than their discography.