BTS released their behind the scenes video of the BBMAs today, which shows them weaving in and out of the dressing rooms of stars who summoned them, while others randomly approach them for photos. The stars include John Legend, Chainsmokers, Lil Poop, Post Malone, DJ Khaled, Khalid, etc. Most importantly, Taylor gushes over them (at 18:24) and Pharrell (like others before him) asks them to work together (32:51).
Pharrell: "I mean, we gotta work [together] now... "
RM: "Wow, we're honored to hear that. For real."
Pharrell: "What are you working on next?"
RM: "We're coming back [to the States] for the tour in August."
Pharrell: "When can we carve some time?"
RM: "We'll make our time."
Source
BTS have everyone relevant after them. If they make the right decisions, they'll have a hit.